[zstd] Reuse the ZSTD_CCtx more often with small data.

This commit is contained in:
Nick Terrell 2018-08-21 14:20:02 -07:00 committed by Nick Terrell
parent 9d6ed9def3
commit 924944e471
3 changed files with 28 additions and 13 deletions

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@ -192,6 +192,7 @@ typedef struct {
BYTE* llCode;
BYTE* mlCode;
BYTE* ofCode;
size_t maxNbSeq;
U32 longLengthID; /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */
U32 longLengthPos;
} seqStore_t;

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@ -931,33 +931,44 @@ typedef enum { ZSTDb_not_buffered, ZSTDb_buffered } ZSTD_buffered_policy_e;
/* ZSTD_sufficientBuff() :
* check internal buffers exist for streaming if buffPol == ZSTDb_buffered .
* Note : they are assumed to be correctly sized if ZSTD_equivalentCParams()==1 */
static U32 ZSTD_sufficientBuff(size_t bufferSize1, size_t blockSize1,
static U32 ZSTD_sufficientBuff(size_t bufferSize1, size_t maxNbSeq1,
ZSTD_buffered_policy_e buffPol2,
ZSTD_compressionParameters cParams2,
U64 pledgedSrcSize)
{
size_t const windowSize2 = MAX(1, (size_t)MIN(((U64)1 << cParams2.windowLog), pledgedSrcSize));
size_t const blockSize2 = MIN(ZSTD_BLOCKSIZE_MAX, windowSize2);
size_t const maxNbSeq2 = blockSize2 / ((cParams2.searchLength == 3) ? 3 : 4);
size_t const neededBufferSize2 = (buffPol2==ZSTDb_buffered) ? windowSize2 + blockSize2 : 0;
DEBUGLOG(4, "ZSTD_sufficientBuff: is windowSize2=%u <= wlog1=%u",
(U32)windowSize2, cParams2.windowLog);
DEBUGLOG(4, "ZSTD_sufficientBuff: is blockSize2=%u <= blockSize1=%u",
(U32)blockSize2, (U32)blockSize1);
return (blockSize2 <= blockSize1) /* seqStore space depends on blockSize */
& (neededBufferSize2 <= bufferSize1);
DEBUGLOG(4, "ZSTD_sufficientBuff: is neededBufferSize2=%u <= bufferSize1=%u",
(U32)neededBufferSize2, bufferSize1);
DEBUGLOG(4, "ZSTD_sufficientBuff: is maxNbSeq2=%u <= maxNbSeq1=%u",
(U32)maxNbSeq2, (U32)maxNbSeq1);
return (maxNbSeq2 <= maxNbSeq1) & (neededBufferSize2 <= bufferSize1);
}
/** Equivalence for resetCCtx purposes */
static U32 ZSTD_equivalentParams(ZSTD_CCtx_params params1,
ZSTD_CCtx_params params2,
size_t buffSize1, size_t blockSize1,
size_t buffSize1, size_t maxNbSeq1,
ZSTD_buffered_policy_e buffPol2,
U64 pledgedSrcSize)
{
DEBUGLOG(4, "ZSTD_equivalentParams: pledgedSrcSize=%u", (U32)pledgedSrcSize);
return ZSTD_equivalentCParams(params1.cParams, params2.cParams) &&
ZSTD_equivalentLdmParams(params1.ldmParams, params2.ldmParams) &&
ZSTD_sufficientBuff(buffSize1, blockSize1, buffPol2, params2.cParams, pledgedSrcSize);
if (!ZSTD_equivalentCParams(params1.cParams, params2.cParams)) {
DEBUGLOG(4, "ZSTD_equivalentCParams() == 0");
return 0;
}
if (!ZSTD_equivalentLdmParams(params1.ldmParams, params2.ldmParams)) {
DEBUGLOG(4, "ZSTD_equivalentLdmParams() == 0");
return 0;
}
if (!ZSTD_sufficientBuff(buffSize1, maxNbSeq1, buffPol2, params2.cParams,
pledgedSrcSize)) {
DEBUGLOG(4, "ZSTD_sufficientBuff() == 0");
return 0;
}
return 1;
}
static void ZSTD_reset_compressedBlockState(ZSTD_compressedBlockState_t* bs)
@ -1085,8 +1096,8 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
if (crp == ZSTDcrp_continue) {
if (ZSTD_equivalentParams(zc->appliedParams, params,
zc->inBuffSize, zc->blockSize,
zbuff, pledgedSrcSize)) {
zc->inBuffSize, zc->seqStore.maxNbSeq,
zbuff, pledgedSrcSize)) {
DEBUGLOG(4, "ZSTD_equivalentParams()==1 -> continue mode (wLog1=%u, blockSize1=%zu)",
zc->appliedParams.cParams.windowLog, zc->blockSize);
zc->workSpaceOversizedDuration += (zc->workSpaceOversizedDuration > 0); /* if it was too large, it still is */
@ -1197,6 +1208,7 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
ptr = ZSTD_reset_matchState(&zc->blockState.matchState, ptr, &params.cParams, crp, /* forCCtx */ 1);
/* sequences storage */
zc->seqStore.maxNbSeq = maxNbSeq;
zc->seqStore.sequencesStart = (seqDef*)ptr;
ptr = zc->seqStore.sequencesStart + maxNbSeq;
zc->seqStore.llCode = (BYTE*) ptr;
@ -1647,6 +1659,7 @@ void ZSTD_seqToCodes(const seqStore_t* seqStorePtr)
BYTE* const mlCodeTable = seqStorePtr->mlCode;
U32 const nbSeq = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
U32 u;
assert(nbSeq <= seqStorePtr->maxNbSeq);
for (u=0; u<nbSeq; u++) {
U32 const llv = sequences[u].litLength;
U32 const mlv = sequences[u].matchLength;

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@ -314,6 +314,7 @@ MEM_STATIC void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const v
pos, (U32)litLength, (U32)mlBase+MINMATCH, (U32)offsetCode);
}
#endif
assert((size_t)(seqStorePtr->sequences - seqStorePtr->sequencesStart) < seqStorePtr->maxNbSeq);
/* copy Literals */
assert(seqStorePtr->lit + litLength <= seqStorePtr->litStart + 128 KB);
ZSTD_wildcopy(seqStorePtr->lit, literals, litLength);