[BUG] really slow GPU parsing of parquet file

[revans2]

Describe the bug
I have a parquet file that is very slow to unsnap on the GPU, but is very fast on the CPU.

Steps/Code to reproduce bug
I am happy to share the file with whom ever, it is a 326 MB parquet file based off of some data from a TPC-DS run for the store sales table with decimal data instead of doubles for money related columns.

Schema:
message spark_schema {
  optional int32 ss_sold_date_sk;
  optional int32 ss_item_sk;
  optional int64 ss_ticket_number;
  optional int32 ss_quantity;
  optional int32 ss_net_paid (DECIMAL(7,2));
  optional int32 ss_net_profit (DECIMAL(7,2));
}

For me all I have to do is to read the data in and it takes about 1.8 seconds to do it, where as on the CPU through Spark it typically takes about 300 ms single threaded (including some computation at the end/spark overhead).

Expected behavior
When I use nsys profile it shows that nearly all of the time 98% is being taken by the unsnap kernel.
I realize that there are not that many columns (6) and that there are only 9 row groups, but there are about 701 data/dictionary pages so I would expect to be able to unsnap the pages all in parallel and see some kind of a speed up, but instead it is much much slower. I also didn't see much if any data size skew between the pages (at least according to the parquet CLI tool).

Environment overview (please complete the following information)
Bare metal desktop with a V100 16 GB GPU in it (cuda 10.1)

Environment details

Click here to see environment details

 **git***
 commit 11ebc3e089b3da786d6d6cf71596d8d2404a6d04 (HEAD -> branch-0.18, origin/branch-0.18)
 Author: Robert (Bobby) Evans <[email protected]>
 Date:   Mon Jan 11 13:22:25 2021 -0600
 
 Adds in JNI support for creating an list column from existing columns(#7112)
 
 Adds in java support to be able to create a list column from other existing columns.
 
 Authors:
 - Robert (Bobby) Evans <[email protected]>
 
 Approvers:
 - Jason Lowe (@jlowe)
 
 URL: https://github.com/rapidsai/cudf/pull/7112
 **git submodules***
 
 ***OS Information***
 DISTRIB_ID=Ubuntu
 DISTRIB_RELEASE=18.04
 DISTRIB_CODENAME=bionic
 DISTRIB_DESCRIPTION="Ubuntu 18.04.5 LTS"
 NAME="Ubuntu"
 VERSION="18.04.5 LTS (Bionic Beaver)"
 ID=ubuntu
 ID_LIKE=debian
 PRETTY_NAME="Ubuntu 18.04.5 LTS"
 VERSION_ID="18.04"
 HOME_URL="https://www.ubuntu.com/"
 SUPPORT_URL="https://help.ubuntu.com/"
 BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
 PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
 VERSION_CODENAME=bionic
 UBUNTU_CODENAME=bionic
 Linux roberte-desktop 4.15.0-130-generic #134-Ubuntu SMP Tue Jan 5 20:46:26 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
 
 ***GPU Information***
 Mon Jan 11 16:16:06 2021
 +-----------------------------------------------------------------------------+
 | NVIDIA-SMI 450.102.04   Driver Version: 450.102.04   CUDA Version: 11.0     |
 |-------------------------------+----------------------+----------------------+
 | GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
 | Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
 |                               |                      |               MIG M. |
 |===============================+======================+======================|
 |   0  GeForce GT 710      Off  | 00000000:17:00.0 N/A |                  N/A |
 | 50%   46C    P8    N/A /  N/A |    689MiB /  1993MiB |     N/A      Default |
 |                               |                      |                  N/A |
 +-------------------------------+----------------------+----------------------+
 |   1  Tesla V100-PCIE...  Off  | 00000000:65:00.0 Off |                    0 |
 | N/A   42C    P0    27W / 250W |      0MiB / 16160MiB |      0%      Default |
 |                               |                      |                  N/A |
 +-------------------------------+----------------------+----------------------+
 
 +-----------------------------------------------------------------------------+
 | Processes:                                                                  |
 |  GPU   GI   CI        PID   Type   Process name                  GPU Memory |
 |        ID   ID                                                   Usage      |
 |=============================================================================|
 |  No running processes found                                                 |
 +-----------------------------------------------------------------------------+
 
 ***CPU***
 Architecture:        x86_64
 CPU op-mode(s):      32-bit, 64-bit
 Byte Order:          Little Endian
 CPU(s):              12
 On-line CPU(s) list: 0-11
 Thread(s) per core:  2
 Core(s) per socket:  6
 Socket(s):           1
 NUMA node(s):        1
 Vendor ID:           GenuineIntel
 CPU family:          6
 Model:               85
 Model name:          Intel(R) Core(TM) i7-7800X CPU @ 3.50GHz
 Stepping:            4
 CPU MHz:             1200.021
 CPU max MHz:         4000.0000
 CPU min MHz:         1200.0000
 BogoMIPS:            6999.82
 Virtualization:      VT-x
 L1d cache:           32K
 L1i cache:           32K
 L2 cache:            1024K
 L3 cache:            8448K
 NUMA node0 CPU(s):   0-11
 Flags:               fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ssbd mba ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm mpx rdt_a avx512f avx512dq rdseed adx smap clflushopt clwb intel_pt avx512cd avx512bw avx512vl xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts hwp hwp_act_window hwp_epp hwp_pkg_req md_clear flush_l1d
 
 ***CMake***
 /home/roberte/miniconda3/envs/cudf_dev/bin/cmake
 cmake version 3.19.1
 
 CMake suite maintained and supported by Kitware (kitware.com/cmake).
 
 ***g++***
 /usr/bin/g++
 g++ (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
 Copyright (C) 2017 Free Software Foundation, Inc.
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 
 
 ***nvcc***
 /usr/local/cuda-10.1/bin/nvcc
 nvcc: NVIDIA (R) Cuda compiler driver
 Copyright (c) 2005-2019 NVIDIA Corporation
 Built on Sun_Jul_28_19:07:16_PDT_2019
 Cuda compilation tools, release 10.1, V10.1.243
 
 ***Python***
 /home/roberte/miniconda3/envs/cudf_dev/bin/python
 Python 3.7.6
 
 ***Environment Variables***
 PATH                            : /home/roberte/miniconda3/envs/cudf_dev/bin:/home/roberte/miniconda3/condabin:/usr/local/cuda-10.1/bin:/home/roberte/.local/bin:/home/roberte/bin:/usr/local/cuda-10.1/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
 LD_LIBRARY_PATH                 : /usr/local/cuda-10.1/lib64
 NUMBAPRO_NVVM                   :
 NUMBAPRO_LIBDEVICE              :
 CONDA_PREFIX                    : /home/roberte/miniconda3/envs/cudf_dev
 PYTHON_PATH                     :
 
 ***conda packages***
 /home/roberte/miniconda3/condabin/conda
 # packages in environment at /home/roberte/miniconda3/envs/cudf_dev:
 #
 # Name                    Version                   Build  Channel
 _libgcc_mutex             0.1                        main
 abseil-cpp                20200225.2           he1b5a44_0    conda-forge
 alabaster                 0.7.12                   py37_0
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 argon2-cffi               20.1.0           py37h7b6447c_1
 arrow-cpp                 1.0.1           py37hf00d4d6_5_cuda    conda-forge
 arrow-cpp-proc            2.0.0                      cuda    conda-forge
 async_generator           1.10             py37h28b3542_0
 attrs                     20.3.0             pyhd3eb1b0_0
 aws-sdk-cpp               1.7.164              hc831370_1    conda-forge
 babel                     2.8.0                      py_0
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 black                     19.10b0                    py_4    conda-forge
 bleach                    3.2.1                      py_0
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 brotli                    1.0.9                he6710b0_2
 brotlipy                  0.7.0           py37h7b6447c_1000
 bzip2                     1.0.8                h7b6447c_0
 c-ares                    1.16.1               h7b6447c_0
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 certifi                   2020.12.5        py37h89c1867_0    conda-forge
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 cfgv                      2.0.1                      py_0    conda-forge
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 click                     7.1.2                      py_0
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 cmake                     3.19.1               h1f3970d_0    conda-forge
 cmake-format              0.6.11             pyh9f0ad1d_0    conda-forge
 cmake_setuptools          0.1.3                      py_0    rapidsai
 colorama                  0.4.4              pyh9f0ad1d_0    conda-forge
 commonmark                0.9.1                      py_0
 configparser              5.0.0                    pypi_0    pypi
 cryptography              3.1.1            py37h1ba5d50_0
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 krb5                      1.18.2               h173b8e3_0
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 mistune                   0.8.4           py37h14c3975_1001
 more-itertools            8.5.0                      py_0
 msgpack-python            1.0.0            py37hfd86e86_1
 nbclient                  0.5.1                      py_0
 nbconvert                 6.0.7                    py37_0
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 nbsphinx                  0.7.1              pyh9f0ad1d_0    conda-forge
 nccl                      2.8.3.1              h8b44402_0    conda-forge
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 nest-asyncio              1.4.1                      py_0
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 numba                     0.49.1           py37h0da4684_0    conda-forge
 numpy                     1.17.5           py37h95a1406_0    conda-forge
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 nvtx                      0.2.1            py37h8f50634_2    conda-forge
 olefile                   0.46                     py37_0
 openssl                   1.1.1h               h516909a_0    conda-forge
 packaging                 20.8               pyhd3deb0d_0    conda-forge
 pandas                    1.1.4            py37h10a2094_0    conda-forge
 pandoc                    1.19.2                        0    conda-forge
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 py                        1.9.0                      py_0
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 pysocks                   1.7.1                    py37_1
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 pytest-benchmark          3.2.3              pyh9f0ad1d_0    conda-forge
 pytest-forked             1.3.0                    pypi_0    pypi
 pytest-xdist              2.1.0                    pypi_0    pypi
 python                    3.7.6           cpython_h8356626_6    conda-forge
 python-dateutil           2.8.1                      py_0
 python_abi                3.7                     1_cp37m    conda-forge
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 pyzmq                     19.0.2           py37he6710b0_1
 rapidjson                 1.1.0             he1b5a44_1002    conda-forge
 re2                       2020.08.01           he1b5a44_0    conda-forge
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 zstd                      1.4.5                h9ceee32_0

Additional context
I am running this on 11ebc3e

I tried to do a bit of profiling with nsight compute, but I am not an expert on any of this so I couldn't come up with much of what might be wrong/off about this.

[github-actions]

This issue has been labeled inactive-30d due to no recent activity in the past 30 days. Please close this issue if no further response or action is needed. Otherwise, please respond with a comment indicating any updates or changes to the original issue and/or confirm this issue still needs to be addressed. This issue will be labeled inactive-90d if there is no activity in the next 60 days.

[jlowe]

This issue is still valid.

[github-actions]

This issue has been labeled inactive-30d due to no recent activity in the past 30 days. Please close this issue if no further response or action is needed. Otherwise, please respond with a comment indicating any updates or changes to the original issue and/or confirm this issue still needs to be addressed. This issue will be labeled inactive-90d if there is no activity in the next 60 days.

[revans2]

This is still valid

[vuule]

@revans2 what is the driver version you are/were using?

[revans2]

Sorry I was out on vacation for the past week.

Tue Apr 13 15:52:46 2021       
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 450.102.04   Driver Version: 450.102.04   CUDA Version: 11.0     |
|-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|                               |                      |               MIG M. |
|===============================+======================+======================|
|   0  GeForce GT 710      On   | 00000000:17:00.0 N/A |                  N/A |
| 50%   48C    P0    N/A /  N/A |    711MiB /  1993MiB |     N/A      Default |
|                               |                      |                  N/A |
+-------------------------------+----------------------+----------------------+
|   1  Tesla V100-PCIE...  On   | 00000000:65:00.0 Off |                    0 |
| N/A   44C    P0    27W / 250W |      0MiB / 16160MiB |      0%      Default |
|                               |                      |                  N/A |
+-------------------------------+----------------------+----------------------+
                                                                               
+-----------------------------------------------------------------------------+
| Processes:                                                                  |
|  GPU   GI   CI        PID   Type   Process name                  GPU Memory |
|        ID   ID                                                   Usage      |
|=============================================================================|
|  No running processes found                                                 |

[revans2]

But I am running with the 10.1 runtime. I will upgrade to 11.2 soon-ish and see if it fixes the issue.

[elstehle]

Fixed by #7975 and #7962