ddidderr/zstd-rs
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

add faster block splitting heuristic, suitable for dfast strategy

Browse Source
This commit is contained in:
Yann Collet
2024-10-24 14:37:00 -07:00
parent 2366a87ddc
commit da2c0dffd8
3 changed files with 22 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/compress/zstd_compress.c
+5 -3
View File
@@ -4507,11 +4507,13 @@ static size_t ZSTD_optimalBlockSize(ZSTD_CCtx* cctx, const void* src, size_t src
/* dynamic splitting has a cpu cost for analysis,
* due to that cost it's only used for higher levels */
if (strat >= ZSTD_btopt)
return ZSTD_splitBlock(src, blockSizeMax, split_lvl3, cctx->tmpWorkspace, cctx->tmpWkspSize);
return ZSTD_splitBlock(src, blockSizeMax, 3, cctx->tmpWorkspace, cctx->tmpWkspSize);
if (strat >= ZSTD_lazy2)
return ZSTD_splitBlock(src, blockSizeMax, split_lvl2, cctx->tmpWorkspace, cctx->tmpWkspSize);
return ZSTD_splitBlock(src, blockSizeMax, 2, cctx->tmpWorkspace, cctx->tmpWkspSize);
if (strat >= ZSTD_greedy)
return ZSTD_splitBlock(src, blockSizeMax, split_lvl1, cctx->tmpWorkspace, cctx->tmpWkspSize);
return ZSTD_splitBlock(src, blockSizeMax, 1, cctx->tmpWorkspace, cctx->tmpWkspSize);
if (strat >= ZSTD_dfast)
return ZSTD_splitBlock(src, blockSizeMax, 0, cctx->tmpWorkspace, cctx->tmpWkspSize);
/* blind split strategy
* heuristic value, tested as being "generally better".
* no cpu cost, but can over-split homegeneous data.