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SD Card Benchmarks

This is a thorough test of more and less familiar ESP32 SD Card access methods. My journey began when I discovered the same problem described in this issue.

This repository is related to my article ESP32 SD Card Optimization

Tests:

  • Write Sequential, variable block sizes
  • Read Sequential, variable block sizes
  • Write Random, variable block sizes
  • Read Random, variable block sizes
  • Write Random aligned, variable block sizes
  • Read Random aligned, variable block sizes

Data

  • Write Time
  • Read Time
  • Block Size: 512 bytes, 1k, 2k, 4k, 8k, 16k, 32k, 64k

TODO

Known Issues

  • SD card is not unmounting properly, need to remove and reinsert the card when completing the SPI tests

Basic Configuration

  • ESP32 WROVER 240Mhz + 80Mhz PSRAM
  • Disabled WDT
  • FATFS LFN in External RAM, Fast Seek Buffer 64.

Results

Alt text

Original fatfs

SPI

Name: SL32G
Type: SDHC/SDXC
Speed: 20 MHz
Size: 30436MB

128 bytes buffer (ESP32 newlib default)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,628ms  ┃  628    ┃  512 KB  ┃  322,044    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  643ms    ┃  1,592  ┃  512 KB  ┃  815,377    ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,294ms  ┃  395    ┃  512 KB  ┃  405,168    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  637ms    ┃  803    ┃  512 KB  ┃  823,058    ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  779ms    ┃  328    ┃  512 KB  ┃  673,026    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  633ms    ┃  404    ┃  512 KB  ┃  828,259    ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  647ms    ┃  197    ┃  512 KB  ┃  810,336    ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  631ms    ┃  202    ┃  512 KB  ┃  830,884    ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  583ms    ┃  109    ┃  512 KB  ┃  899,293    ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  631ms    ┃  101    ┃  512 KB  ┃  830,884    ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  571ms    ┃  56     ┃  512 KB  ┃  918,192    ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  630ms    ┃  50     ┃  512 KB  ┃  832,203    ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,695ms  ┃  9      ┃  512 KB  ┃  309,314    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  652ms    ┃  24     ┃  512 KB  ┃  804,122    ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,708ms  ┃  4      ┃  512 KB  ┃  306,960    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  673ms    ┃  11     ┃  512 KB  ┃  779,031    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,517ms  ┃  157    ┃  512 KB  ┃  80,449     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,259ms  ┃  813    ┃  512 KB  ┃  416,432    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,223ms  ┃  121    ┃  512 KB  ┃  124,150    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  945ms    ┃  541    ┃  512 KB  ┃  554,802    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  9,279ms  ┃  27     ┃  512 KB  ┃  56,502     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  786ms    ┃  325    ┃  512 KB  ┃  667,033    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,894ms  ┃  18     ┃  512 KB  ┃  76,049     ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  708ms    ┃  180    ┃  512 KB  ┃  740,519    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,524ms  ┃  18     ┃  512 KB  ┃  148,776    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  668ms    ┃  95     ┃  512 KB  ┃  784,862    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  1,787ms  ┃  17     ┃  512 KB  ┃  293,390    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  648ms    ┃  49     ┃  512 KB  ┃  809,086    ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,814ms  ┃  5      ┃  512 KB  ┃  186,314    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  665ms    ┃  24     ┃  512 KB  ┃  788,403    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,441ms  ┃  3      ┃  512 KB  ┃  214,784    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  678ms    ┃  11     ┃  512 KB  ┃  773,286    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  2,738ms  ┃  373    ┃  512 KB  ┃  191,485    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  687ms    ┃  1,490  ┃  512 KB  ┃  763,155    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,940ms  ┃  263    ┃  512 KB  ┃  270,251    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  656ms    ┃  780    ┃  512 KB  ┃  799,219    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  1,418ms  ┃  180    ┃  512 KB  ┃  369,737    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  643ms    ┃  398    ┃  512 KB  ┃  815,377    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  821ms    ┃  155    ┃  512 KB  ┃  638,596    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  636ms    ┃  201    ┃  512 KB  ┃  824,352    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  404ms    ┃  158    ┃  512 KB  ┃  1,297,742  ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  633ms    ┃  101    ┃  512 KB  ┃  828,259    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  746ms    ┃  42     ┃  512 KB  ┃  702,798    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  632ms    ┃  50     ┃  512 KB  ┃  829,569    ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,062ms  ┃  7      ┃  512 KB  ┃  254,261    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  655ms    ┃  24     ┃  512 KB  ┃  800,439    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,447ms  ┃  3      ┃  512 KB  ┃  214,257    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  673ms    ┃  11     ┃  512 KB  ┃  779,031    ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

2048 bytes buffer (using setvbuf)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  688ms    ┃  1,488  ┃  512 KB  ┃  762,046    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  384ms    ┃  2,666  ┃  512 KB  ┃  1,365,333  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  885ms    ┃  578    ┃  512 KB  ┃  592,415    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  383ms    ┃  1,336  ┃  512 KB  ┃  1,368,898  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  837ms    ┃  305    ┃  512 KB  ┃  626,389    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  381ms    ┃  671    ┃  512 KB  ┃  1,376,083  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  723ms    ┃  177    ┃  512 KB  ┃  725,156    ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  379ms    ┃  337    ┃  512 KB  ┃  1,383,345  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  590ms    ┃  108    ┃  512 KB  ┃  888,623    ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  378ms    ┃  169    ┃  512 KB  ┃  1,387,005  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  577ms    ┃  55     ┃  512 KB  ┃  908,644    ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  377ms    ┃  84     ┃  512 KB  ┃  1,390,684  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,653ms  ┃  9      ┃  512 KB  ┃  317,173    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  398ms    ┃  40     ┃  512 KB  ┃  1,317,306  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,686ms  ┃  4      ┃  512 KB  ┃  310,965    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  420ms    ┃  19     ┃  512 KB  ┃  1,248,304  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,722ms  ┃  152    ┃  512 KB  ┃  77,995     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  3,265ms  ┃  313    ┃  512 KB  ┃  160,578    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,744ms  ┃  107    ┃  512 KB  ┃  110,516    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,634ms  ┃  313    ┃  512 KB  ┃  320,861    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  7,266ms  ┃  35     ┃  512 KB  ┃  72,156     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  683ms    ┃  374    ┃  512 KB  ┃  767,625    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,988ms  ┃  25     ┃  512 KB  ┃  105,109    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  603ms    ┃  212    ┃  512 KB  ┃  869,466    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,946ms  ┃  21     ┃  512 KB  ┃  177,966    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  557ms    ┃  114    ┃  512 KB  ┃  941,271    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,099ms  ┃  15     ┃  512 KB  ┃  249,779    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  535ms    ┃  59     ┃  512 KB  ┃  979,977    ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,407ms  ┃  6      ┃  512 KB  ┃  217,818    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  571ms    ┃  28     ┃  512 KB  ┃  918,192    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,135ms  ┃  3      ┃  512 KB  ┃  245,568    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  586ms    ┃  13     ┃  512 KB  ┃  894,689    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  2,699ms  ┃  379    ┃  512 KB  ┃  194,252    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  1,624ms  ┃  630    ┃  512 KB  ┃  322,837    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,439ms  ┃  355    ┃  512 KB  ┃  364,341    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  814ms    ┃  628    ┃  512 KB  ┃  644,088    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  1,050ms  ┃  243    ┃  512 KB  ┃  499,321    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  403ms    ┃  635    ┃  512 KB  ┃  1,300,962  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  587ms    ┃  218    ┃  512 KB  ┃  893,165    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  389ms    ┃  329    ┃  512 KB  ┃  1,347,784  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  1,087ms  ┃  58     ┃  512 KB  ┃  482,325    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  384ms    ┃  166    ┃  512 KB  ┃  1,365,333  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  1,070ms  ┃  29     ┃  512 KB  ┃  489,988    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  379ms    ┃  84     ┃  512 KB  ┃  1,383,345  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,315ms  ┃  6      ┃  512 KB  ┃  226,474    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  402ms    ┃  39     ┃  512 KB  ┃  1,304,199  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  1,833ms  ┃  4      ┃  512 KB  ┃  286,027    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  421ms    ┃  19     ┃  512 KB  ┃  1,245,339  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

4096 bytes buffer (using setvbuf)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time      ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  509ms     ┃  2,011  ┃  512 KB  ┃  1,030,035  ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  346ms     ┃  2,959  ┃  512 KB  ┃  1,515,283  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  706ms     ┃  725    ┃  512 KB  ┃  742,617    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  341ms     ┃  1,501  ┃  512 KB  ┃  1,537,501  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  703ms     ┃  364    ┃  512 KB  ┃  745,786    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  339ms     ┃  755    ┃  512 KB  ┃  1,546,572  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  658ms     ┃  194    ┃  512 KB  ┃  796,790    ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  338ms     ┃  378    ┃  512 KB  ┃  1,551,147  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  588ms     ┃  108    ┃  512 KB  ┃  891,646    ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  337ms     ┃  189    ┃  512 KB  ┃  1,555,750  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  573ms     ┃  55     ┃  512 KB  ┃  914,987    ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  337ms     ┃  94     ┃  512 KB  ┃  1,555,750  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  2,173ms   ┃  7      ┃  512 KB  ┃  241,273    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  358ms     ┃  44     ┃  512 KB  ┃  1,464,491  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,741ms   ┃  4      ┃  512 KB  ┃  301,141    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  379ms     ┃  21     ┃  512 KB  ┃  1,383,345  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,510ms   ┃  157    ┃  512 KB  ┃  80,535     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  5,078ms   ┃  201    ┃  512 KB  ┃  103,246    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,389ms   ┃  116    ┃  512 KB  ┃  119,455    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  2,564ms   ┃  199    ┃  512 KB  ┃  204,480    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  10,051ms  ┃  25     ┃  512 KB  ┃  52,162     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,284ms   ┃  199    ┃  512 KB  ┃  408,323    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,200ms   ┃  24     ┃  512 KB  ┃  100,824    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  577ms     ┃  221    ┃  512 KB  ┃  908,644    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,171ms   ┃  29     ┃  512 KB  ┃  241,496    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  537ms     ┃  119    ┃  512 KB  ┃  976,327    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,577ms   ┃  12     ┃  512 KB  ┃  203,448    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  525ms     ┃  60     ┃  512 KB  ┃  998,643    ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,579ms   ┃  6      ┃  512 KB  ┃  203,291    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  482ms     ┃  33     ┃  512 KB  ┃  1,087,734  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,222ms   ┃  3      ┃  512 KB  ┃  235,953    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  528ms     ┃  15     ┃  512 KB  ┃  992,969    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,826ms   ┃  267    ┃  512 KB  ┃  137,032    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  2,803ms   ┃  365    ┃  512 KB  ┃  187,045    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  2,007ms   ┃  255    ┃  512 KB  ┃  261,229    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,410ms   ┃  363    ┃  512 KB  ┃  371,835    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  1,062ms   ┃  241    ┃  512 KB  ┃  493,679    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  701ms     ┃  365    ┃  512 KB  ┃  747,914    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  488ms     ┃  262    ┃  512 KB  ┃  1,074,360  ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  348ms     ┃  367    ┃  512 KB  ┃  1,506,574  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  448ms     ┃  142    ┃  512 KB  ┃  1,170,285  ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  342ms     ┃  187    ┃  512 KB  ┃  1,533,005  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  743ms     ┃  43     ┃  512 KB  ┃  705,636    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  339ms     ┃  94     ┃  512 KB  ┃  1,546,572  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,724ms   ┃  5      ┃  512 KB  ┃  192,469    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  360ms     ┃  44     ┃  512 KB  ┃  1,456,355  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,429ms   ┃  3      ┃  512 KB  ┃  215,845    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  379ms     ┃  21     ┃  512 KB  ┃  1,383,345  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

unbuffered (using write/read)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,485ms  ┃  689    ┃  512 KB  ┃  353,055    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  545ms    ┃  1,878  ┃  512 KB  ┃  961,996    ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,076ms  ┃  475    ┃  512 KB  ┃  487,256    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  458ms    ┃  1,117  ┃  512 KB  ┃  1,144,733  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  591ms    ┃  433    ┃  512 KB  ┃  887,120    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  373ms    ┃  686    ┃  512 KB  ┃  1,405,597  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  444ms    ┃  288    ┃  512 KB  ┃  1,180,828  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  331ms    ┃  386    ┃  512 KB  ┃  1,583,951  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  380ms    ┃  168    ┃  512 KB  ┃  1,379,705  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  310ms    ┃  206    ┃  512 KB  ┃  1,691,251  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  369ms    ┃  86     ┃  512 KB  ┃  1,420,834  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  303ms    ┃  105    ┃  512 KB  ┃  1,730,323  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,488ms  ┃  10     ┃  512 KB  ┃  352,344    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  548ms    ┃  29     ┃  512 KB  ┃  956,729    ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,499ms  ┃  5      ┃  512 KB  ┃  349,758    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  569ms    ┃  14     ┃  512 KB  ┃  921,420    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,556ms  ┃  156    ┃  512 KB  ┃  79,970     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,211ms  ┃  845    ┃  512 KB  ┃  432,938    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,993ms  ┃  128    ┃  512 KB  ┃  131,301    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  871ms    ┃  587    ┃  512 KB  ┃  601,938    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  7,639ms  ┃  33     ┃  512 KB  ┃  68,633     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  673ms    ┃  380    ┃  512 KB  ┃  779,031    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,254ms  ┃  30     ┃  512 KB  ┃  123,245    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  571ms    ┃  224    ┃  512 KB  ┃  918,192    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,523ms  ┃  18     ┃  512 KB  ┃  148,818    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  538ms    ┃  118    ┃  512 KB  ┃  974,513    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,430ms  ┃  13     ┃  512 KB  ┃  215,756    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  493ms    ┃  64     ┃  512 KB  ┃  1,063,464  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,622ms  ┃  6      ┃  512 KB  ┃  199,957    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  564ms    ┃  28     ┃  512 KB  ┃  929,588    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,644ms  ┃  3      ┃  512 KB  ┃  198,293    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  573ms    ┃  13     ┃  512 KB  ┃  914,987    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,414ms  ┃  299    ┃  512 KB  ┃  153,570    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  598ms    ┃  1,712  ┃  512 KB  ┃  876,735    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,547ms  ┃  330    ┃  512 KB  ┃  338,906    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  484ms    ┃  1,057  ┃  512 KB  ┃  1,083,239  ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  1,418ms  ┃  180    ┃  512 KB  ┃  369,737    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  387ms    ┃  661    ┃  512 KB  ┃  1,354,749  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  1,210ms  ┃  105    ┃  512 KB  ┃  433,295    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  337ms    ┃  379    ┃  512 KB  ┃  1,555,750  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  391ms    ┃  163    ┃  512 KB  ┃  1,340,890  ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  312ms    ┃  205    ┃  512 KB  ┃  1,680,410  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  742ms    ┃  43     ┃  512 KB  ┃  706,587    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  300ms    ┃  106    ┃  512 KB  ┃  1,747,626  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,050ms  ┃  7      ┃  512 KB  ┃  255,750    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  550ms    ┃  29     ┃  512 KB  ┃  953,250    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,374ms  ┃  3      ┃  512 KB  ┃  220,845    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  569ms    ┃  14     ┃  512 KB  ┃  921,420    ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

SDMMC

Name: SL32G
Type: SDHC/SDXC
Speed: 40 MHz
Size: 30436MB

128 bytes buffer (ESP32 newlib default)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,290ms  ┃  793    ┃  512 KB  ┃  406,424    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  495ms    ┃  2,068  ┃  512 KB  ┃  1,059,167  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  961ms    ┃  532    ┃  512 KB  ┃  545,565    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  488ms    ┃  1,049  ┃  512 KB  ┃  1,074,360  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  604ms    ┃  423    ┃  512 KB  ┃  868,026    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  485ms    ┃  527    ┃  512 KB  ┃  1,081,006  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  438ms    ┃  292    ┃  512 KB  ┃  1,197,004  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  483ms    ┃  265    ┃  512 KB  ┃  1,085,482  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  377ms    ┃  169    ┃  512 KB  ┃  1,390,684  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  482ms    ┃  132    ┃  512 KB  ┃  1,087,734  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  361ms    ┃  88     ┃  512 KB  ┃  1,452,321  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  482ms    ┃  66     ┃  512 KB  ┃  1,087,734  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,499ms  ┃  10     ┃  512 KB  ┃  349,758    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  501ms    ┃  31     ┃  512 KB  ┃  1,046,483  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,506ms  ┃  5      ┃  512 KB  ┃  348,132    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  524ms    ┃  15     ┃  512 KB  ┃  1,000,549  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,926ms  ┃  172    ┃  512 KB  ┃  88,472     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  957ms    ┃  1,070  ┃  512 KB  ┃  547,845    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,529ms  ┃  113    ┃  512 KB  ┃  115,762    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  718ms    ┃  713    ┃  512 KB  ┃  730,206    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  8,326ms  ┃  30     ┃  512 KB  ┃  62,969     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  601ms    ┃  425    ┃  512 KB  ┃  872,359    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,972ms  ┃  32     ┃  512 KB  ┃  131,995    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  541ms    ┃  236    ┃  512 KB  ┃  969,109    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,143ms  ┃  20     ┃  512 KB  ┃  166,811    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  511ms    ┃  125    ┃  512 KB  ┃  1,026,003  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,076ms  ┃  15     ┃  512 KB  ┃  252,547    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  497ms    ┃  64     ┃  512 KB  ┃  1,054,905  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,055ms  ┃  7      ┃  512 KB  ┃  255,127    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  513ms    ┃  31     ┃  512 KB  ┃  1,022,003  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,254ms  ┃  3      ┃  512 KB  ┃  232,603    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  529ms    ┃  15     ┃  512 KB  ┃  991,092    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  2,800ms  ┃  365    ┃  512 KB  ┃  187,245    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  550ms    ┃  1,861  ┃  512 KB  ┃  953,250    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,180ms  ┃  433    ┃  512 KB  ┃  444,311    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  516ms    ┃  992    ┃  512 KB  ┃  1,016,062  ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  782ms    ┃  327    ┃  512 KB  ┃  670,445    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  497ms    ┃  515    ┃  512 KB  ┃  1,054,905  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  258ms    ┃  496    ┃  512 KB  ┃  2,032,124  ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  489ms    ┃  261    ┃  512 KB  ┃  1,072,163  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  209ms    ┃  306    ┃  512 KB  ┃  2,508,555  ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  484ms    ┃  132    ┃  512 KB  ┃  1,083,239  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  141ms    ┃  226    ┃  512 KB  ┃  3,718,354  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  481ms    ┃  66     ┃  512 KB  ┃  1,089,995  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  1,953ms  ┃  8      ┃  512 KB  ┃  268,452    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  506ms    ┃  31     ┃  512 KB  ┃  1,036,142  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,167ms  ┃  3      ┃  512 KB  ┃  241,941    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  525ms    ┃  15     ┃  512 KB  ┃  998,643    ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

2048 bytes buffer (using setvbuf)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  690ms    ┃  1,484  ┃  512 KB  ┃  759,837    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  215ms    ┃  4,762  ┃  512 KB  ┃  2,438,548  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  654ms    ┃  782    ┃  512 KB  ┃  801,663    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  210ms    ┃  2,438  ┃  512 KB  ┃  2,496,609  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  607ms    ┃  421    ┃  512 KB  ┃  863,736    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  208ms    ┃  1,230  ┃  512 KB  ┃  2,520,615  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  440ms    ┃  290    ┃  512 KB  ┃  1,191,563  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  206ms    ┃  621    ┃  512 KB  ┃  2,545,087  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  379ms    ┃  168    ┃  512 KB  ┃  1,383,345  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  205ms    ┃  312    ┃  512 KB  ┃  2,557,502  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  364ms    ┃  87     ┃  512 KB  ┃  1,440,351  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  205ms    ┃  156    ┃  512 KB  ┃  2,557,502  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,497ms  ┃  10     ┃  512 KB  ┃  350,225    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  221ms    ┃  72     ┃  512 KB  ┃  2,372,343  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,510ms  ┃  5      ┃  512 KB  ┃  347,210    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  245ms    ┃  32     ┃  512 KB  ┃  2,139,951  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,034ms  ┃  169    ┃  512 KB  ┃  86,888     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  2,333ms  ┃  438    ┃  512 KB  ┃  224,726    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,035ms  ┃  126    ┃  512 KB  ┃  129,935    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,174ms  ┃  436    ┃  512 KB  ┃  446,582    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  8,947ms  ┃  28     ┃  512 KB  ┃  58,599     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  494ms    ┃  518    ┃  512 KB  ┃  1,061,311  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,982ms  ┃  32     ┃  512 KB  ┃  131,664    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  431ms    ┃  296    ┃  512 KB  ┃  1,216,445  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,754ms  ┃  17     ┃  512 KB  ┃  139,661    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  395ms    ┃  162    ┃  512 KB  ┃  1,327,311  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,840ms  ┃  11     ┃  512 KB  ┃  184,608    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  387ms    ┃  82     ┃  512 KB  ┃  1,354,749  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,342ms  ┃  6      ┃  512 KB  ┃  223,863    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  402ms    ┃  39     ┃  512 KB  ┃  1,304,199  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,504ms  ┃  3      ┃  512 KB  ┃  209,380    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  419ms    ┃  19     ┃  512 KB  ┃  1,251,284  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  2,725ms  ┃  375    ┃  512 KB  ┃  192,399    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  910ms    ┃  1,125  ┃  512 KB  ┃  576,140    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,430ms  ┃  358    ┃  512 KB  ┃  366,634    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  452ms    ┃  1,132  ┃  512 KB  ┃  1,159,929  ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  771ms    ┃  332    ┃  512 KB  ┃  680,010    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  222ms    ┃  1,153  ┃  512 KB  ┃  2,361,657  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  295ms    ┃  433    ┃  512 KB  ┃  1,777,247  ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  212ms    ┃  603    ┃  512 KB  ┃  2,473,056  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  526ms    ┃  121    ┃  512 KB  ┃  996,745    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  207ms    ┃  309    ┃  512 KB  ┃  2,532,792  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  533ms    ┃  60     ┃  512 KB  ┃  983,654    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  205ms    ┃  156    ┃  512 KB  ┃  2,557,502  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  1,823ms  ┃  8      ┃  512 KB  ┃  287,596    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  225ms    ┃  71     ┃  512 KB  ┃  2,330,168  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  1,877ms  ┃  4      ┃  512 KB  ┃  279,322    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  245ms    ┃  32     ┃  512 KB  ┃  2,139,951  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

4096 bytes buffer (using setvbuf)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  294ms    ┃  3,482  ┃  512 KB  ┃  1,783,292  ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  169ms    ┃  6,059  ┃  512 KB  ┃  3,102,295  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  289ms    ┃  1,771  ┃  512 KB  ┃  1,814,145  ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  164ms    ┃  3,121  ┃  512 KB  ┃  3,196,878  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  287ms    ┃  891    ┃  512 KB  ┃  1,826,787  ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  162ms    ┃  1,580  ┃  512 KB  ┃  3,236,345  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  245ms    ┃  522    ┃  512 KB  ┃  2,139,951  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  160ms    ┃  800    ┃  512 KB  ┃  3,276,800  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  171ms    ┃  374    ┃  512 KB  ┃  3,066,011  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  160ms    ┃  400    ┃  512 KB  ┃  3,276,800  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  156ms    ┃  205    ┃  512 KB  ┃  3,360,820  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  158ms    ┃  202    ┃  512 KB  ┃  3,318,278  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,393ms  ┃  11     ┃  512 KB  ┃  376,373    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  174ms    ┃  91     ┃  512 KB  ┃  3,013,149  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,522ms  ┃  5      ┃  512 KB  ┃  344,473    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  199ms    ┃  40     ┃  512 KB  ┃  2,634,613  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,996ms  ┃  170    ┃  512 KB  ┃  87,439     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  3,561ms  ┃  287    ┃  512 KB  ┃  147,230    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,165ms  ┃  122    ┃  512 KB  ┃  125,879    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,789ms  ┃  286    ┃  512 KB  ┃  293,062    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  8,402ms  ┃  30     ┃  512 KB  ┃  62,400     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  904ms    ┃  283    ┃  512 KB  ┃  579,964    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,324ms  ┃  29     ┃  512 KB  ┃  121,250    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  411ms    ┃  311    ┃  512 KB  ┃  1,275,639  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,334ms  ┃  14     ┃  512 KB  ┃  120,970    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  376ms    ┃  170    ┃  512 KB  ┃  1,394,382  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,087ms  ┃  15     ┃  512 KB  ┃  251,216    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  354ms    ┃  90     ┃  512 KB  ┃  1,481,039  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,455ms  ┃  6      ┃  512 KB  ┃  213,559    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  350ms    ┃  45     ┃  512 KB  ┃  1,497,965  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  1,998ms  ┃  4      ┃  512 KB  ┃  262,406    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  413ms    ┃  19     ┃  512 KB  ┃  1,269,462  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,614ms  ┃  283    ┃  512 KB  ┃  145,071    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  1,353ms  ┃  756    ┃  512 KB  ┃  387,500    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  963ms    ┃  531    ┃  512 KB  ┃  544,431    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  678ms    ┃  755    ┃  512 KB  ┃  773,286    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  1,180ms  ┃  216    ┃  512 KB  ┃  444,311    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  340ms    ┃  752    ┃  512 KB  ┃  1,542,023  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  297ms    ┃  430    ┃  512 KB  ┃  1,765,279  ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  167ms    ┃  766    ┃  512 KB  ┃  3,139,449  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  528ms    ┃  121    ┃  512 KB  ┃  992,969    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  162ms    ┃  395    ┃  512 KB  ┃  3,236,345  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  190ms    ┃  168    ┃  512 KB  ┃  2,759,410  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  159ms    ┃  201    ┃  512 KB  ┃  3,297,408  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,352ms  ┃  6      ┃  512 KB  ┃  222,911    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  179ms    ┃  89     ┃  512 KB  ┃  2,928,983  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,181ms  ┃  3      ┃  512 KB  ┃  240,388    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  199ms    ┃  40     ┃  512 KB  ┃  2,634,613  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

unbuffered (using write/read)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,536ms  ┃  666    ┃  512 KB  ┃  341,333    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  401ms    ┃  2,553  ┃  512 KB  ┃  1,307,451  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,195ms  ┃  428    ┃  512 KB  ┃  438,734    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  283ms    ┃  1,809  ┃  512 KB  ┃  1,852,607  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  616ms    ┃  415    ┃  512 KB  ┃  851,116    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  201ms    ┃  1,273  ┃  512 KB  ┃  2,608,398  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  444ms    ┃  288    ┃  512 KB  ┃  1,180,828  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  153ms    ┃  836    ┃  512 KB  ┃  3,426,718  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  381ms    ┃  167    ┃  512 KB  ┃  1,376,083  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  129ms    ┃  496    ┃  512 KB  ┃  4,064,248  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  370ms    ┃  86     ┃  512 KB  ┃  1,416,994  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  121ms    ┃  264    ┃  512 KB  ┃  4,332,958  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,502ms  ┃  10     ┃  512 KB  ┃  349,059    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  392ms    ┃  40     ┃  512 KB  ┃  1,337,469  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,513ms  ┃  5      ┃  512 KB  ┃  346,522    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  416ms    ┃  19     ┃  512 KB  ┃  1,260,307  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,300ms  ┃  193    ┃  512 KB  ┃  98,922     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  929ms    ┃  1,102  ┃  512 KB  ┃  564,357    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,593ms  ┃  111    ┃  512 KB  ┃  114,149    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  655ms    ┃  781    ┃  512 KB  ┃  800,439    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  7,364ms  ┃  34     ┃  512 KB  ┃  71,196     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  489ms    ┃  523    ┃  512 KB  ┃  1,072,163  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,321ms  ┃  29     ┃  512 KB  ┃  121,334    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  391ms    ┃  327    ┃  512 KB  ┃  1,340,890  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,695ms  ┃  23     ┃  512 KB  ┃  194,541    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  378ms    ┃  169    ┃  512 KB  ┃  1,387,005  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,730ms  ┃  11     ┃  512 KB  ┃  192,046    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  350ms    ┃  91     ┃  512 KB  ┃  1,497,965  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,662ms  ┃  6      ┃  512 KB  ┃  196,952    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  403ms    ┃  39     ┃  512 KB  ┃  1,300,962  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,112ms  ┃  3      ┃  512 KB  ┃  248,242    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  420ms    ┃  19     ┃  512 KB  ┃  1,248,304  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,224ms  ┃  317    ┃  512 KB  ┃  162,620    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  442ms    ┃  2,316  ┃  512 KB  ┃  1,186,171  ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,542ms  ┃  332    ┃  512 KB  ┃  340,005    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  301ms    ┃  1,700  ┃  512 KB  ┃  1,741,820  ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  457ms    ┃  560    ┃  512 KB  ┃  1,147,238  ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  210ms    ┃  1,219  ┃  512 KB  ┃  2,496,609  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  637ms    ┃  200    ┃  512 KB  ┃  823,058    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  157ms    ┃  815    ┃  512 KB  ┃  3,339,414  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  546ms    ┃  117    ┃  512 KB  ┃  960,234    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  131ms    ┃  488    ┃  512 KB  ┃  4,002,198  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  163ms    ┃  196    ┃  512 KB  ┃  3,216,490  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  121ms    ┃  264    ┃  512 KB  ┃  4,332,958  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  1,794ms  ┃  8      ┃  512 KB  ┃  292,245    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  396ms    ┃  40     ┃  512 KB  ┃  1,323,959  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  1,991ms  ┃  4      ┃  512 KB  ┃  263,328    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  416ms    ┃  19     ┃  512 KB  ┃  1,260,307  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

Modified fatfs component

add exfat support in ffconf.h (under components/fastfs/src)

#define FF_FS_EXFAT		1

modify vfs_fat.c (under components/fatfs/vfs) to add support for (fast seek)[http://elm-chan.org/fsw/ff/doc/config.html#use_fastseek] from:

if(!(fat_mode_conv(flags) & (FA_WRITE))) {
        DWORD *clmt_mem =  ff_memalloc(sizeof(DWORD) * CONFIG_FATFS_FAST_SEEK_BUFFER_SIZE);

to:

if((fat_mode_conv(flags) & (FA_READ))) {
    DWORD *clmt_mem =  ff_memalloc(sizeof(DWORD) * CONFIG_FATFS_FAST_SEEK_BUFFER_SIZE);

the meaning of this modification is whenever a file is opened for read (not just read as the original code states) it will attempt to build the fast seek map.

Note: this modification makes the behavior of esp32 non-standard, you may have to modify the flags used in your fopen.

SPI

Name: SL32G
Type: SDHC/SDXC
Speed: 20 MHz
Size: 30436MB

128 bytes buffer (ESP32 newlib default)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,520ms  ┃  673    ┃  512 KB  ┃  344,926    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  638ms    ┃  1,605  ┃  512 KB  ┃  821,768    ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,269ms  ┃  403    ┃  512 KB  ┃  413,150    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  628ms    ┃  815    ┃  512 KB  ┃  834,853    ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  758ms    ┃  337    ┃  512 KB  ┃  691,672    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  622ms    ┃  411    ┃  512 KB  ┃  842,906    ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  629ms    ┃  203    ┃  512 KB  ┃  833,526    ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  619ms    ┃  206    ┃  512 KB  ┃  846,991    ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  565ms    ┃  113    ┃  512 KB  ┃  927,943    ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  618ms    ┃  103    ┃  512 KB  ┃  848,362    ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  553ms    ┃  57     ┃  512 KB  ┃  948,079    ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  617ms    ┃  51     ┃  512 KB  ┃  849,737    ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,646ms  ┃  9      ┃  512 KB  ┃  318,522    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  640ms    ┃  25     ┃  512 KB  ┃  819,200    ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,658ms  ┃  4      ┃  512 KB  ┃  316,217    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  660ms    ┃  12     ┃  512 KB  ┃  794,375    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,682ms  ┃  153    ┃  512 KB  ┃  78,462     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,214ms  ┃  843    ┃  512 KB  ┃  431,868    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,900ms  ┃  104    ┃  512 KB  ┃  106,997    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  916ms    ┃  558    ┃  512 KB  ┃  572,366    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  7,984ms  ┃  32     ┃  512 KB  ┃  65,667     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  766ms    ┃  334    ┃  512 KB  ┃  684,449    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,208ms  ┃  30     ┃  512 KB  ┃  124,593    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  692ms    ┃  184    ┃  512 KB  ┃  757,641    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,936ms  ┃  21     ┃  512 KB  ┃  178,572    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  656ms    ┃  97     ┃  512 KB  ┃  799,219    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,171ms  ┃  14     ┃  512 KB  ┃  241,496    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  636ms    ┃  50     ┃  512 KB  ┃  824,352    ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,343ms  ┃  6      ┃  512 KB  ┃  223,767    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  652ms    ┃  24     ┃  512 KB  ┃  804,122    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  1,904ms  ┃  4      ┃  512 KB  ┃  275,361    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  666ms    ┃  12     ┃  512 KB  ┃  787,219    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,472ms  ┃  294    ┃  512 KB  ┃  151,004    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  664ms    ┃  1,542  ┃  512 KB  ┃  789,590    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  2,175ms  ┃  235    ┃  512 KB  ┃  241,051    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  640ms    ┃  800    ┃  512 KB  ┃  819,200    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  1,339ms  ┃  191    ┃  512 KB  ┃  391,551    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  629ms    ┃  406    ┃  512 KB  ┃  833,526    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  900ms    ┃  142    ┃  512 KB  ┃  582,542    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  625ms    ┃  204    ┃  512 KB  ┃  838,860    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  382ms    ┃  167    ┃  512 KB  ┃  1,372,481  ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  619ms    ┃  103    ┃  512 KB  ┃  846,991    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  413ms    ┃  77     ┃  512 KB  ┃  1,269,462  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  618ms    ┃  51     ┃  512 KB  ┃  848,362    ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,477ms  ┃  6      ┃  512 KB  ┃  211,662    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  643ms    ┃  24     ┃  512 KB  ┃  815,377    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,028ms  ┃  3      ┃  512 KB  ┃  258,524    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  661ms    ┃  12     ┃  512 KB  ┃  793,173    ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

2048 bytes buffer (using setvbuf)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  625ms    ┃  1,638  ┃  512 KB  ┃  838,860    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  394ms    ┃  2,598  ┃  512 KB  ┃  1,330,680  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  619ms    ┃  827    ┃  512 KB  ┃  846,991    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  390ms    ┃  1,312  ┃  512 KB  ┃  1,344,328  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  590ms    ┃  433    ┃  512 KB  ┃  888,623    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  387ms    ┃  661    ┃  512 KB  ┃  1,354,749  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  444ms    ┃  288    ┃  512 KB  ┃  1,180,828  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  383ms    ┃  334    ┃  512 KB  ┃  1,368,898  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  384ms    ┃  166    ┃  512 KB  ┃  1,365,333  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  381ms    ┃  167    ┃  512 KB  ┃  1,376,083  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  369ms    ┃  86     ┃  512 KB  ┃  1,420,834  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  380ms    ┃  84     ┃  512 KB  ┃  1,379,705  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,462ms  ┃  10     ┃  512 KB  ┃  358,610    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  401ms    ┃  39     ┃  512 KB  ┃  1,307,451  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,469ms  ┃  5      ┃  512 KB  ┃  356,901    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  422ms    ┃  18     ┃  512 KB  ┃  1,242,388  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,280ms  ┃  163    ┃  512 KB  ┃  83,485     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  3,215ms  ┃  318    ┃  512 KB  ┃  163,075    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,600ms  ┃  91     ┃  512 KB  ┃  93,622     ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,604ms  ┃  319    ┃  512 KB  ┃  326,862    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  7,197ms  ┃  35     ┃  512 KB  ┃  72,848     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  681ms    ┃  375    ┃  512 KB  ┃  769,879    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,690ms  ┃  27     ┃  512 KB  ┃  111,788    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  601ms    ┃  212    ┃  512 KB  ┃  872,359    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,294ms  ┃  19     ┃  512 KB  ┃  159,164    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  563ms    ┃  113    ┃  512 KB  ┃  931,239    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,152ms  ┃  10     ┃  512 KB  ┃  166,335    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  519ms    ┃  61     ┃  512 KB  ┃  1,010,188  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,351ms  ┃  6      ┃  512 KB  ┃  223,006    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  553ms    ┃  28     ┃  512 KB  ┃  948,079    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,831ms  ┃  2      ┃  512 KB  ┃  185,195    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  583ms    ┃  13     ┃  512 KB  ┃  899,293    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  2,686ms  ┃  381    ┃  512 KB  ┃  195,192    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  1,582ms  ┃  647    ┃  512 KB  ┃  331,408    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  2,055ms  ┃  249    ┃  512 KB  ┃  255,127    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  794ms    ┃  644    ┃  512 KB  ┃  660,312    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  668ms    ┃  383    ┃  512 KB  ┃  784,862    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  393ms    ┃  651    ┃  512 KB  ┃  1,334,066  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  1,572ms  ┃  81     ┃  512 KB  ┃  333,516    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  386ms    ┃  331    ┃  512 KB  ┃  1,358,259  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  1,109ms  ┃  57     ┃  512 KB  ┃  472,757    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  383ms    ┃  167    ┃  512 KB  ┃  1,368,898  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  364ms    ┃  87     ┃  512 KB  ┃  1,440,351  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  381ms    ┃  83     ┃  512 KB  ┃  1,376,083  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,328ms  ┃  6      ┃  512 KB  ┃  225,209    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  404ms    ┃  39     ┃  512 KB  ┃  1,297,742  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,948ms  ┃  2      ┃  512 KB  ┃  177,845    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  423ms    ┃  18     ┃  512 KB  ┃  1,239,451  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

4096 bytes buffer (using setvbuf)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  503ms    ┃  2,035  ┃  512 KB  ┃  1,042,322  ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  349ms    ┃  2,934  ┃  512 KB  ┃  1,502,257  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  498ms    ┃  1,028  ┃  512 KB  ┃  1,052,787  ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  344ms    ┃  1,488  ┃  512 KB  ┃  1,524,093  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  496ms    ┃  516    ┃  512 KB  ┃  1,057,032  ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  342ms    ┃  748    ┃  512 KB  ┃  1,533,005  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  450ms    ┃  284    ┃  512 KB  ┃  1,165,084  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  341ms    ┃  375    ┃  512 KB  ┃  1,537,501  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  381ms    ┃  167    ┃  512 KB  ┃  1,376,083  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  339ms    ┃  188    ┃  512 KB  ┃  1,546,572  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  369ms    ┃  86     ┃  512 KB  ┃  1,420,834  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  337ms    ┃  94     ┃  512 KB  ┃  1,555,750  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,535ms  ┃  10     ┃  512 KB  ┃  341,555    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  358ms    ┃  44     ┃  512 KB  ┃  1,464,491  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,482ms  ┃  5      ┃  512 KB  ┃  353,770    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  379ms    ┃  21     ┃  512 KB  ┃  1,383,345  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,580ms  ┃  155    ┃  512 KB  ┃  79,679     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  5,082ms  ┃  201    ┃  512 KB  ┃  103,165    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,000ms  ┃  102    ┃  512 KB  ┃  104,857    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  2,525ms  ┃  202    ┃  512 KB  ┃  207,638    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  7,214ms  ┃  35     ┃  512 KB  ┃  72,676     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,283ms  ┃  199    ┃  512 KB  ┃  408,642    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,623ms  ┃  27     ┃  512 KB  ┃  113,408    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  559ms    ┃  228    ┃  512 KB  ┃  937,903    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,238ms  ┃  19     ┃  512 KB  ┃  161,917    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  535ms    ┃  119    ┃  512 KB  ┃  979,977    ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,013ms  ┃  15     ┃  512 KB  ┃  260,451    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  508ms    ┃  62     ┃  512 KB  ┃  1,032,062  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,031ms  ┃  7      ┃  512 KB  ┃  258,142    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  510ms    ┃  31     ┃  512 KB  ┃  1,028,015  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  1,905ms  ┃  4      ┃  512 KB  ┃  275,216    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  546ms    ┃  14     ┃  512 KB  ┃  960,234    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,871ms  ┃  264    ┃  512 KB  ┃  135,439    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  2,763ms  ┃  370    ┃  512 KB  ┃  189,753    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,955ms  ┃  261    ┃  512 KB  ┃  268,178    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,380ms  ┃  371    ┃  512 KB  ┃  379,918    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  666ms    ┃  384    ┃  512 KB  ┃  787,219    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  694ms    ┃  368    ┃  512 KB  ┃  755,458    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  920ms    ┃  139    ┃  512 KB  ┃  569,878    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  343ms    ┃  373    ┃  512 KB  ┃  1,528,536  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  735ms    ┃  87     ┃  512 KB  ┃  713,317    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  339ms    ┃  188    ┃  512 KB  ┃  1,546,572  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  359ms    ┃  89     ┃  512 KB  ┃  1,460,412  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  339ms    ┃  94     ┃  512 KB  ┃  1,546,572  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  1,962ms  ┃  8      ┃  512 KB  ┃  267,221    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  361ms    ┃  44     ┃  512 KB  ┃  1,452,321  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,284ms  ┃  3      ┃  512 KB  ┃  229,548    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  380ms    ┃  21     ┃  512 KB  ┃  1,379,705  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

unbuffered (using write/read)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,727ms  ┃  592    ┃  512 KB  ┃  303,583    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  550ms    ┃  1,861  ┃  512 KB  ┃  953,250    ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,299ms  ┃  394    ┃  512 KB  ┃  403,608    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  463ms    ┃  1,105  ┃  512 KB  ┃  1,132,371  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  785ms    ┃  326    ┃  512 KB  ┃  667,882    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  375ms    ┃  682    ┃  512 KB  ┃  1,398,101  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  655ms    ┃  195    ┃  512 KB  ┃  800,439    ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  331ms    ┃  386    ┃  512 KB  ┃  1,583,951  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  592ms    ┃  108    ┃  512 KB  ┃  885,621    ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  310ms    ┃  206    ┃  512 KB  ┃  1,691,251  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  580ms    ┃  55     ┃  512 KB  ┃  903,944    ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  302ms    ┃  105    ┃  512 KB  ┃  1,736,052  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,701ms  ┃  9      ┃  512 KB  ┃  308,223    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  546ms    ┃  29     ┃  512 KB  ┃  960,234    ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,713ms  ┃  4      ┃  512 KB  ┃  306,064    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  567ms    ┃  14     ┃  512 KB  ┃  924,670    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,974ms  ┃  171    ┃  512 KB  ┃  87,761     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,159ms  ┃  883    ┃  512 KB  ┃  452,362    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,966ms  ┃  103    ┃  512 KB  ┃  105,575    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  843ms    ┃  607    ┃  512 KB  ┃  621,931    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  8,959ms  ┃  28     ┃  512 KB  ┃  58,520     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  655ms    ┃  390    ┃  512 KB  ┃  800,439    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,562ms  ┃  23     ┃  512 KB  ┃  94,262     ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  560ms    ┃  228    ┃  512 KB  ┃  936,228    ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,731ms  ┃  17     ┃  512 KB  ┃  140,522    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  512ms    ┃  125    ┃  512 KB  ┃  1,024,000  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,306ms  ┃  9      ┃  512 KB  ┃  158,586    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  489ms    ┃  65     ┃  512 KB  ┃  1,072,163  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,395ms  ┃  6      ┃  512 KB  ┃  218,909    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  557ms    ┃  28     ┃  512 KB  ┃  941,271    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,743ms  ┃  2      ┃  512 KB  ┃  191,136    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  572ms    ┃  13     ┃  512 KB  ┃  916,587    ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,457ms  ┃  296    ┃  512 KB  ┃  151,659    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  568ms    ┃  1,802  ┃  512 KB  ┃  923,042    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,536ms  ┃  333    ┃  512 KB  ┃  341,333    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  472ms    ┃  1,084  ┃  512 KB  ┃  1,110,779  ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  1,406ms  ┃  182    ┃  512 KB  ┃  372,893    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  380ms    ┃  673    ┃  512 KB  ┃  1,379,705  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  1,232ms  ┃  103    ┃  512 KB  ┃  425,558    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  334ms    ┃  383    ┃  512 KB  ┃  1,569,724  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  770ms    ┃  83     ┃  512 KB  ┃  680,893    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  310ms    ┃  206    ┃  512 KB  ┃  1,691,251  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  727ms    ┃  44     ┃  512 KB  ┃  721,166    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  303ms    ┃  105    ┃  512 KB  ┃  1,730,323  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,415ms  ┃  6      ┃  512 KB  ┃  217,096    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  549ms    ┃  29     ┃  512 KB  ┃  954,987    ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,673ms  ┃  2      ┃  512 KB  ┃  196,142    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  568ms    ┃  14     ┃  512 KB  ┃  923,042    ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

SDMMC

Name: SL32G
Type: SDHC/SDXC
Speed: 40 MHz
Size: 30436MB

128 bytes buffer (ESP32 newlib default)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,289ms  ┃  794    ┃  512 KB  ┃  406,740    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  461ms    ┃  2,221  ┃  512 KB  ┃  1,137,284  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  961ms    ┃  532    ┃  512 KB  ┃  545,565    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  457ms    ┃  1,120  ┃  512 KB  ┃  1,147,238  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  604ms    ┃  423    ┃  512 KB  ┃  868,026    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  454ms    ┃  563    ┃  512 KB  ┃  1,154,819  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  434ms    ┃  294    ┃  512 KB  ┃  1,208,036  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  453ms    ┃  282    ┃  512 KB  ┃  1,157,368  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  376ms    ┃  170    ┃  512 KB  ┃  1,394,382  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  452ms    ┃  141    ┃  512 KB  ┃  1,159,929  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  361ms    ┃  88     ┃  512 KB  ┃  1,452,321  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  452ms    ┃  70     ┃  512 KB  ┃  1,159,929  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,496ms  ┃  10     ┃  512 KB  ┃  350,459    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  472ms    ┃  33     ┃  512 KB  ┃  1,110,779  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,508ms  ┃  5      ┃  512 KB  ┃  347,671    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  494ms    ┃  16     ┃  512 KB  ┃  1,061,311  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,295ms  ┃  193    ┃  512 KB  ┃  99,015     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  887ms    ┃  1,154  ┃  512 KB  ┃  591,080    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,087ms  ┃  100    ┃  512 KB  ┃  103,064    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  667ms    ┃  767    ┃  512 KB  ┃  786,038    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  8,276ms  ┃  30     ┃  512 KB  ┃  63,350     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  561ms    ┃  456    ┃  512 KB  ┃  934,559    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,097ms  ┃  31     ┃  512 KB  ┃  127,968    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  507ms    ┃  252    ┃  512 KB  ┃  1,034,098  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,067ms  ┃  20     ┃  512 KB  ┃  170,944    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  480ms    ┃  133    ┃  512 KB  ┃  1,092,266  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,146ms  ┃  14     ┃  512 KB  ┃  244,309    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  467ms    ┃  68     ┃  512 KB  ┃  1,122,672  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  1,993ms  ┃  8      ┃  512 KB  ┃  263,064    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  486ms    ┃  32     ┃  512 KB  ┃  1,078,781  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,141ms  ┃  3      ┃  512 KB  ┃  244,879    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  499ms    ┃  16     ┃  512 KB  ┃  1,050,677  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,206ms  ┃  319    ┃  512 KB  ┃  163,533    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  488ms    ┃  2,098  ┃  512 KB  ┃  1,074,360  ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,384ms  ┃  369    ┃  512 KB  ┃  378,820    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  470ms    ┃  1,089  ┃  512 KB  ┃  1,115,506  ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  1,099ms  ┃  232    ┃  512 KB  ┃  477,059    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  460ms    ┃  556    ┃  512 KB  ┃  1,139,756  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  309ms    ┃  414    ┃  512 KB  ┃  1,696,724  ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  456ms    ┃  280    ┃  512 KB  ┃  1,149,754  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  163ms    ┃  392    ┃  512 KB  ┃  3,216,490  ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  454ms    ┃  140    ┃  512 KB  ┃  1,154,819  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  494ms    ┃  64     ┃  512 KB  ┃  1,061,311  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  451ms    ┃  70     ┃  512 KB  ┃  1,162,501  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  1,658ms  ┃  9      ┃  512 KB  ┃  316,217    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  476ms    ┃  33     ┃  512 KB  ┃  1,101,445  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,608ms  ┃  3      ┃  512 KB  ┃  201,030    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  494ms    ┃  16     ┃  512 KB  ┃  1,061,311  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

2048 bytes buffer (using setvbuf)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  529ms    ┃  1,935  ┃  512 KB  ┃  991,092    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  209ms    ┃  4,899  ┃  512 KB  ┃  2,508,555  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  445ms    ┃  1,150  ┃  512 KB  ┃  1,178,175  ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  204ms    ┃  2,509  ┃  512 KB  ┃  2,570,039  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  395ms    ┃  648    ┃  512 KB  ┃  1,327,311  ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  202ms    ┃  1,267  ┃  512 KB  ┃  2,595,485  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  228ms    ┃  561    ┃  512 KB  ┃  2,299,508  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  201ms    ┃  636    ┃  512 KB  ┃  2,608,398  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  170ms    ┃  376    ┃  512 KB  ┃  3,084,047  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  200ms    ┃  320    ┃  512 KB  ┃  2,621,440  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  155ms    ┃  206    ┃  512 KB  ┃  3,382,503  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  200ms    ┃  160    ┃  512 KB  ┃  2,621,440  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,267ms  ┃  12     ┃  512 KB  ┃  413,802    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  218ms    ┃  73     ┃  512 KB  ┃  2,404,990  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,280ms  ┃  6      ┃  512 KB  ┃  409,600    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  241ms    ┃  33     ┃  512 KB  ┃  2,175,468  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,685ms  ┃  180    ┃  512 KB  ┃  92,223     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  2,253ms  ┃  454    ┃  512 KB  ┃  232,706    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,717ms  ┃  137    ┃  512 KB  ┃  141,051    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,127ms  ┃  454    ┃  512 KB  ┃  465,206    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  8,413ms  ┃  30     ┃  512 KB  ┃  62,318     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  470ms    ┃  544    ┃  512 KB  ┃  1,115,506  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,270ms  ┃  39     ┃  512 KB  ┃  160,332    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  415ms    ┃  308    ┃  512 KB  ┃  1,263,344  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,334ms  ┃  19     ┃  512 KB  ┃  157,254    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  399ms    ┃  160    ┃  512 KB  ┃  1,314,005  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,219ms  ┃  14     ┃  512 KB  ┃  236,272    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  362ms    ┃  88     ┃  512 KB  ┃  1,448,309  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,077ms  ┃  7      ┃  512 KB  ┃  252,425    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  393ms    ┃  40     ┃  512 KB  ┃  1,334,066  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  1,980ms  ┃  4      ┃  512 KB  ┃  264,791    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  408ms    ┃  19     ┃  512 KB  ┃  1,285,019  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  3,605ms  ┃  284    ┃  512 KB  ┃  145,433    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  843ms    ┃  1,214  ┃  512 KB  ┃  621,931    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,795ms  ┃  285    ┃  512 KB  ┃  292,082    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  422ms    ┃  1,213  ┃  512 KB  ┃  1,242,388  ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  762ms    ┃  335    ┃  512 KB  ┃  688,041    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  207ms    ┃  1,236  ┃  512 KB  ┃  2,532,792  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  264ms    ┃  484    ┃  512 KB  ┃  1,985,939  ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  203ms    ┃  630    ┃  512 KB  ┃  2,582,699  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  246ms    ┃  260    ┃  512 KB  ┃  2,131,252  ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  202ms    ┃  316    ┃  512 KB  ┃  2,595,485  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  839ms    ┃  38     ┃  512 KB  ┃  624,896    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  201ms    ┃  159    ┃  512 KB  ┃  2,608,398  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,448ms  ┃  6      ┃  512 KB  ┃  214,169    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  222ms    ┃  72     ┃  512 KB  ┃  2,361,657  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,269ms  ┃  3      ┃  512 KB  ┃  231,065    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  242ms    ┃  33     ┃  512 KB  ┃  2,166,479  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

4096 bytes buffer (using setvbuf)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  293ms    ┃  3,494  ┃  512 KB  ┃  1,789,378  ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  165ms    ┃  6,206  ┃  512 KB  ┃  3,177,503  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  289ms    ┃  1,771  ┃  512 KB  ┃  1,814,145  ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  160ms    ┃  3,200  ┃  512 KB  ┃  3,276,800  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  286ms    ┃  895    ┃  512 KB  ┃  1,833,174  ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  158ms    ┃  1,620  ┃  512 KB  ┃  3,318,278  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  245ms    ┃  522    ┃  512 KB  ┃  2,139,951  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  157ms    ┃  815    ┃  512 KB  ┃  3,339,414  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  171ms    ┃  374    ┃  512 KB  ┃  3,066,011  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  156ms    ┃  410    ┃  512 KB  ┃  3,360,820  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  156ms    ┃  205    ┃  512 KB  ┃  3,360,820  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  156ms    ┃  205    ┃  512 KB  ┃  3,360,820  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,413ms  ┃  11     ┃  512 KB  ┃  371,046    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  173ms    ┃  92     ┃  512 KB  ┃  3,030,566  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,507ms  ┃  5      ┃  512 KB  ┃  347,901    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  196ms    ┃  40     ┃  512 KB  ┃  2,674,938  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,191ms  ┃  165    ┃  512 KB  ┃  84,685     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  3,456ms  ┃  296    ┃  512 KB  ┃  151,703    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  4,786ms  ┃  106    ┃  512 KB  ┃  109,546    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  1,737ms  ┃  294    ┃  512 KB  ┃  301,835    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  6,933ms  ┃  36     ┃  512 KB  ┃  75,622     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  868ms    ┃  294    ┃  512 KB  ┃  604,018    ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,616ms  ┃  35     ┃  512 KB  ┃  144,991    ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  387ms    ┃  330    ┃  512 KB  ┃  1,354,749  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,784ms  ┃  22     ┃  512 KB  ┃  188,321    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  372ms    ┃  172    ┃  512 KB  ┃  1,409,376  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,029ms  ┃  15     ┃  512 KB  ┃  258,397    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  363ms    ┃  88     ┃  512 KB  ┃  1,444,319  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,950ms  ┃  5      ┃  512 KB  ┃  177,724    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  368ms    ┃  43     ┃  512 KB  ┃  1,424,695  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,031ms  ┃  3      ┃  512 KB  ┃  258,142    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  428ms    ┃  18     ┃  512 KB  ┃  1,224,971  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  2,386ms  ┃  429    ┃  512 KB  ┃  219,735    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  1,303ms  ┃  785    ┃  512 KB  ┃  402,369    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,705ms  ┃  300    ┃  512 KB  ┃  307,500    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  647ms    ┃  791    ┃  512 KB  ┃  810,336    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  837ms    ┃  305    ┃  512 KB  ┃  626,389    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  322ms    ┃  795    ┃  512 KB  ┃  1,628,223  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  256ms    ┃  500    ┃  512 KB  ┃  2,048,000  ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  159ms    ┃  805    ┃  512 KB  ┃  3,297,408  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  589ms    ┃  108    ┃  512 KB  ┃  890,132    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  158ms    ┃  405    ┃  512 KB  ┃  3,318,278  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  177ms    ┃  180    ┃  512 KB  ┃  2,962,079  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  157ms    ┃  203    ┃  512 KB  ┃  3,339,414  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  2,109ms  ┃  7      ┃  512 KB  ┃  248,595    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  177ms    ┃  90     ┃  512 KB  ┃  2,962,079  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  1,866ms  ┃  4      ┃  512 KB  ┃  280,968    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  197ms    ┃  40     ┃  512 KB  ┃  2,661,360  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

unbuffered (using write/read)

┏━━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━━━━━┓
┃  Block   ┃  R/W  ┃  Rnd/Seq  ┃  Sync  ┃  Aligned  ┃  time     ┃  iops   ┃  bytes   ┃  bps        ┃
┣━━━━━━━━━━╋━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━━━╋━━━━━━━━━╋━━━━━━━━━━╋━━━━━━━━━━━━━┫
┃  512     ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,393ms  ┃  735    ┃  512 KB  ┃  376,373    ┃
┃  512     ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  390ms    ┃  2,625  ┃  512 KB  ┃  1,344,328  ┃
┃  1,024   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,178ms  ┃  434    ┃  512 KB  ┃  445,066    ┃
┃  1,024   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  277ms    ┃  1,848  ┃  512 KB  ┃  1,892,736  ┃
┃  2,048   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  601ms    ┃  425    ┃  512 KB  ┃  872,359    ┃
┃  2,048   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  197ms    ┃  1,299  ┃  512 KB  ┃  2,661,360  ┃
┃  4,096   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  432ms    ┃  296    ┃  512 KB  ┃  1,213,629  ┃
┃  4,096   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  150ms    ┃  853    ┃  512 KB  ┃  3,495,253  ┃
┃  8,192   ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  371ms    ┃  172    ┃  512 KB  ┃  1,413,175  ┃
┃  8,192   ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  130ms    ┃  492    ┃  512 KB  ┃  4,032,984  ┃
┃  16,384  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  359ms    ┃  89     ┃  512 KB  ┃  1,460,412  ┃
┃  16,384  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  119ms    ┃  268    ┃  512 KB  ┃  4,405,781  ┃
┃  32,768  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,492ms  ┃  10     ┃  512 KB  ┃  351,399    ┃
┃  32,768  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  391ms    ┃  40     ┃  512 KB  ┃  1,340,890  ┃
┃  65,536  ┃  W    ┃  Seq      ┃  X     ┃  Not      ┃  1,506ms  ┃  5      ┃  512 KB  ┃  348,132    ┃
┃  65,536  ┃  R    ┃  Seq      ┃  X     ┃  Not      ┃  413ms    ┃  19     ┃  512 KB  ┃  1,269,462  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,687ms  ┃  180    ┃  512 KB  ┃  92,190     ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  857ms    ┃  1,194  ┃  512 KB  ┃  611,771    ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  3,766ms  ┃  135    ┃  512 KB  ┃  139,216    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  616ms    ┃  831    ┃  512 KB  ┃  851,116    ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  8,272ms  ┃  30     ┃  512 KB  ┃  63,381     ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  464ms    ┃  551    ┃  512 KB  ┃  1,129,931  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  5,324ms  ┃  24     ┃  512 KB  ┃  98,476     ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  387ms    ┃  330    ┃  512 KB  ┃  1,354,749  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,727ms  ┃  23     ┃  512 KB  ┃  192,258    ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  353ms    ┃  181    ┃  512 KB  ┃  1,485,235  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,591ms  ┃  12     ┃  512 KB  ┃  202,349    ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  352ms    ┃  90     ┃  512 KB  ┃  1,489,454  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,528ms  ┃  6      ┃  512 KB  ┃  207,392    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  402ms    ┃  39     ┃  512 KB  ┃  1,304,199  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  Not      ┃  2,075ms  ┃  3      ┃  512 KB  ┃  252,668    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  Not      ┃  416ms    ┃  19     ┃  512 KB  ┃  1,260,307  ┃
┃  512     ┃  W    ┃  Rnd      ┃  X     ┃  512      ┃  2,528ms  ┃  405    ┃  512 KB  ┃  207,392    ┃
┃  512     ┃  R    ┃  Rnd      ┃  X     ┃  512      ┃  410ms    ┃  2,497  ┃  512 KB  ┃  1,278,751  ┃
┃  1,024   ┃  W    ┃  Rnd      ┃  X     ┃  1,024    ┃  1,563ms  ┃  327    ┃  512 KB  ┃  335,436    ┃
┃  1,024   ┃  R    ┃  Rnd      ┃  X     ┃  1,024    ┃  285ms    ┃  1,796  ┃  512 KB  ┃  1,839,607  ┃
┃  2,048   ┃  W    ┃  Rnd      ┃  X     ┃  2,048    ┃  737ms    ┃  347    ┃  512 KB  ┃  711,381    ┃
┃  2,048   ┃  R    ┃  Rnd      ┃  X     ┃  2,048    ┃  201ms    ┃  1,273  ┃  512 KB  ┃  2,608,398  ┃
┃  4,096   ┃  W    ┃  Rnd      ┃  X     ┃  4,096    ┃  273ms    ┃  468    ┃  512 KB  ┃  1,920,468  ┃
┃  4,096   ┃  R    ┃  Rnd      ┃  X     ┃  4,096    ┃  153ms    ┃  836    ┃  512 KB  ┃  3,426,718  ┃
┃  8,192   ┃  W    ┃  Rnd      ┃  X     ┃  8,192    ┃  254ms    ┃  251    ┃  512 KB  ┃  2,064,125  ┃
┃  8,192   ┃  R    ┃  Rnd      ┃  X     ┃  8,192    ┃  128ms    ┃  500    ┃  512 KB  ┃  4,096,000  ┃
┃  16,384  ┃  W    ┃  Rnd      ┃  X     ┃  16,384   ┃  522ms    ┃  61     ┃  512 KB  ┃  1,004,383  ┃
┃  16,384  ┃  R    ┃  Rnd      ┃  X     ┃  16,384   ┃  119ms    ┃  268    ┃  512 KB  ┃  4,405,781  ┃
┃  32,768  ┃  W    ┃  Rnd      ┃  X     ┃  32,768   ┃  1,733ms  ┃  9      ┃  512 KB  ┃  302,532    ┃
┃  32,768  ┃  R    ┃  Rnd      ┃  X     ┃  32,768   ┃  393ms    ┃  40     ┃  512 KB  ┃  1,334,066  ┃
┃  65,536  ┃  W    ┃  Rnd      ┃  X     ┃  65,536   ┃  2,091ms  ┃  3      ┃  512 KB  ┃  250,735    ┃
┃  65,536  ┃  R    ┃  Rnd      ┃  X     ┃  65,536   ┃  414ms    ┃  19     ┃  512 KB  ┃  1,266,396  ┃
┗━━━━━━━━━━┻━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━━━┻━━━━━━━━━┻━━━━━━━━━━┻━━━━━━━━━━━━━┛

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