allow jobSize to be as low as 512 KB

previous lower limit was 1 MB.

Note : by default, the lowest job size is 2 MB, achieved at level 1.
Even lower job sizes can be achieved by manipulating this value directly,
or manually modifying window sizes to lower amounts.

Updated unit test to ensure that this new limit works fine
(test would fail with previous 1 MB limit).
This commit is contained in:
Yann Collet 2021-05-04 10:54:34 -07:00
parent 6f40571ae2
commit 8f86c29c06
2 changed files with 7 additions and 7 deletions

View File

@ -32,11 +32,11 @@
/* === Constants === */
#ifndef ZSTDMT_NBWORKERS_MAX
#ifndef ZSTDMT_NBWORKERS_MAX /* can be modified at compile time */
# define ZSTDMT_NBWORKERS_MAX 200
#endif
#ifndef ZSTDMT_JOBSIZE_MIN
# define ZSTDMT_JOBSIZE_MIN (1 MB)
#ifndef ZSTDMT_JOBSIZE_MIN /* can be modified at compile time */
# define ZSTDMT_JOBSIZE_MIN (512 KB)
#endif
#define ZSTDMT_JOBLOG_MAX (MEM_32bits() ? 29 : 30)
#define ZSTDMT_JOBSIZE_MAX (MEM_32bits() ? (512 MB) : (1024 MB))

View File

@ -1589,6 +1589,7 @@ static int basicUnitTests(U32 const seed, double compressibility)
DISPLAYLEVEL(3, "test%3i : setting multithreaded parameters : ", testNb++)
{ ZSTD_CCtx_params* params = ZSTD_createCCtxParams();
int const jobSize = 512 KB;
int value;
/* Check that the overlap log and job size are unset. */
CHECK( ZSTD_CCtxParams_getParameter(params, ZSTD_c_overlapLog, &value) );
@ -1597,19 +1598,18 @@ static int basicUnitTests(U32 const seed, double compressibility)
CHECK_EQ(value, 0);
/* Set and check the overlap log and job size. */
CHECK( ZSTD_CCtxParams_setParameter(params, ZSTD_c_overlapLog, 5) );
CHECK( ZSTD_CCtxParams_setParameter(params, ZSTD_c_jobSize, 2 MB) );
CHECK( ZSTD_CCtxParams_setParameter(params, ZSTD_c_jobSize, jobSize) );
CHECK( ZSTD_CCtxParams_getParameter(params, ZSTD_c_overlapLog, &value) );
CHECK_EQ(value, 5);
CHECK( ZSTD_CCtxParams_getParameter(params, ZSTD_c_jobSize, &value) );
CHECK_EQ(value, 2 MB);
CHECK_EQ(value, jobSize);
/* Set the number of workers and check the overlap log and job size. */
CHECK( ZSTD_CCtxParams_setParameter(params, ZSTD_c_nbWorkers, 2) );
CHECK( ZSTD_CCtxParams_getParameter(params, ZSTD_c_overlapLog, &value) );
CHECK_EQ(value, 5);
CHECK( ZSTD_CCtxParams_getParameter(params, ZSTD_c_jobSize, &value) );
CHECK_EQ(value, 2 MB);
CHECK_EQ(value, jobSize);
ZSTD_freeCCtxParams(params);
}
DISPLAYLEVEL(3, "OK \n");