Setting QSV_FREEMEMORY_HEADROOM_PCT to 0 disables memory availability check

docs/ENVIRONMENT_VARIABLES.md

@@ -22,7 +22,7 @@
 | `QSV_RDR_BUFFER_CAPACITY` | reader buffer size (default - 128k (bytes): 131072) |
 | `QSV_SKIP_FORMAT_CHECK` | if set, skips mime-type checking of input files. Set this when optimizing for performance and when encountering false positives as a format check involves scanning the input file to infer the mime-type/format. |
 | `QSV_WTR_BUFFER_CAPACITY` | writer buffer size (default - 512k (bytes): 524288) |
-| `QSV_FREEMEMORY_HEADROOM_PCT` | the percentage of free available memory required when running qsv in "non-streaming" mode (i.e. the entire file needs to be loaded into memory). If the incoming file is greater than the available memory after the headroom is subtracted, qsv will not proceed. See [Memory Management](#memory-management) for more info. (default: (percent) 20 ) |
+| `QSV_FREEMEMORY_HEADROOM_PCT` | the percentage of free available memory required when running qsv in "non-streaming" mode (i.e. the entire file needs to be loaded into memory). If the incoming file is greater than the available memory after the headroom is subtracted, qsv will not proceed. Set to 0 to skip memory check. See [Memory Management](#memory-management) for more info. (default: (percent) 20 ) |
 | `QSV_MEMORY_CHECK` | if set, check if input file size < AVAILABLE memory - HEADROOM (CONSERVATIVE mode) when running in "non-streaming" mode. Otherwise, qsv will only check if the input file size < TOTAL memory - HEADROOM (NORMAL mode). This is done to prevent Out-of-Memory errors. See [Memory Management](#memory-management) for more info. |
 | `QSV_LOG_LEVEL` | desired level (default - off; `error`, `warn`, `info`, `trace`, `debug`). |
 | `QSV_LOG_DIR` | when logging is enabled, the directory where the log files will be stored. If the specified directory does not exist, qsv will attempt to create it. If not set, the log files are created in the directory where qsv was started. See [Logging](docs/Logging.md#logging) for more info. |

dotenv.template

@@ -113,7 +113,8 @@ QSV_WTR_BUFFER_CAPACITY = 524288
 # the percentage of free available memory required when running qsv in
 # "non-streaming" mode (i.e. the entire file needs to be loaded into memory).
 # If the incoming file is greater than the available memory after the headroom
-# is subtracted, qsv will not proceed. See Memory Management for more info.
+# is subtracted, qsv will not proceed. Set to 0 to skip memory check.
+# See Memory Management for more info.
 # (default: (percent) 20 )
 QSV_FREEMEMORY_HEADROOM_PCT = 20
 

src/util.rs

@@ -623,15 +623,21 @@ pub fn mem_file_check(
 
     let conservative_memcheck_work = get_envvar_flag("QSV_MEMORY_CHECK") || conservative_memcheck;
 
+    let mut mem_pct = env::var("QSV_FREEMEMORY_HEADROOM_PCT")
+        .unwrap_or_else(|_| DEFAULT_FREEMEMORY_HEADROOM_PCT.to_string())
+        .parse::<u8>()
+        .unwrap_or(DEFAULT_FREEMEMORY_HEADROOM_PCT);
+
+    // if QSV_FREEMEMORY_HEADROOM_PCT is 0, we skip the memory check
+    if mem_pct == 0 {
+        return Ok(i64::MAX);
+    }
+
     let mut sys = sysinfo::System::new();
     sys.refresh_memory();
     let avail_mem = sys.available_memory();
     let free_swap = sys.free_swap();
     let total_mem = sys.total_memory();
-    let mut mem_pct = env::var("QSV_FREEMEMORY_HEADROOM_PCT")
-        .unwrap_or_else(|_| DEFAULT_FREEMEMORY_HEADROOM_PCT.to_string())
-        .parse::<u8>()
-        .unwrap_or(DEFAULT_FREEMEMORY_HEADROOM_PCT);
 
     // for safety, we don't want to go below 10% memory headroom
     // nor above 90% memory headroom as its too memory-restrictive