AuroraMiddleware/zstd
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

updated ZSTD_estimateCCtxSize()

Browse Source 
added a parameter streaming,
to estimate memory allocation size
when the CCtx is used for streaming (CStream).

Note : this function is not able to estimate
memory cost of a potential internal CDict
which can only happen when starting with ZSTD_initCStream_usingDict()
This commit is contained in:
Yann Collet 2017-05-08 17:07:59 -07:00
parent 791d744279
commit fc5145955a
4 changed files with 24 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
doc/zstd_manual.html
View File

@ -372,7 +372,7 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
<a name="Chapter14"></a><h2>Advanced compression functions</h2><pre></pre>
<pre><b>size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams);
<pre><b>size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams, unsigned streaming);
</b><p> Gives the amount of memory allocated for a ZSTD_CCtx given a set of compression parameters.
`frameContentSize` is an optional parameter, provide `0` if unknown
</p></pre><BR>
@ -382,7 +382,7 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
</p></pre><BR>
<pre><b>size_t ZSTD_sizeof_CCtx(const ZSTD_CCtx* cctx);
</b><p> Gives the amount of memory used by a given ZSTD_CCtx
</b><p> amount of used memory is variable, depending primarily on compression level
</p></pre><BR>
<pre><b>typedef enum {
@ -507,7 +507,7 @@ typedef struct { ZSTD_allocFunction customAlloc; ZSTD_freeFunction customFree; v
<a name="Chapter16"></a><h2>Advanced streaming functions</h2><pre></pre>
<h3>Advanced Streaming compression functions</h3><pre></pre><b><pre>ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem);
size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs); </b>/**< size of CStream is variable, depending primarily on compression level */<b>
size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs); </b>/**< same as ZSTD_sizeof_CCtx */<b>
size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize); </b>/**< pledgedSrcSize must be correct, a size of 0 means unknown. for a frame size of 0 use initCStream_advanced */<b>
size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); </b>/**< note: a dict will not be used if dict == NULL or dictSize < 8 */<b>
size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize,

23
lib/compress/zstd_compress.c
View File

@ -244,7 +244,7 @@ ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, u
}
size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams)
size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams, unsigned streaming)
{
size_t const blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << cParams.windowLog);
U32 const divider = (cParams.searchLength==3) ? 3 : 4;
@ -260,12 +260,17 @@ size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams)
+ entropyScratchSpace_size;
size_t const tableSpace = (chainSize + hSize + h3Size) * sizeof(U32);
size_t const optSpace = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
size_t const optBudget = ((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
+ (ZSTD_OPT_NUM+1)*(sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
size_t const neededSpace = entropySpace + tableSpace + tokenSpace
+ (((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btopt2)) ? optSpace : 0);
size_t const optSpace = ((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btopt2)) ? optBudget : 0;
size_t const neededSpace = entropySpace + tableSpace + tokenSpace + optSpace;
return sizeof(ZSTD_CCtx) + neededSpace;
size_t const inBuffSize = ((size_t)1 << cParams.windowLog) + blockSize;
size_t const outBuffSize = ZSTD_compressBound(blockSize) + 1;
size_t const streamingBudget = inBuffSize + outBuffSize;
size_t const streamingSize = streaming ? streamingBudget : 0;
return sizeof(ZSTD_CCtx) + neededSpace + streamingSize;
}
@ -3194,23 +3199,23 @@ static size_t ZSTD_initCStream_stage2(ZSTD_CStream* zcs,
unsigned long long pledgedSrcSize)
{
assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
zcs->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, (size_t)1 << params.cParams.windowLog);
/* allocate buffers */
{ size_t const neededInBuffSize = (size_t)1 << params.cParams.windowLog;
{ size_t const neededInBuffSize = ((size_t)1 << params.cParams.windowLog) + zcs->blockSize;
if (zcs->inBuffSize < neededInBuffSize) {
zcs->inBuffSize = 0;
ZSTD_free(zcs->inBuff, zcs->customMem);
zcs->inBuff = (char*) ZSTD_malloc(neededInBuffSize, zcs->customMem);
zcs->inBuff = (char*)ZSTD_malloc(neededInBuffSize, zcs->customMem);
if (zcs->inBuff == NULL) return ERROR(memory_allocation);
zcs->inBuffSize = neededInBuffSize;
}
zcs->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, neededInBuffSize);
}
if (zcs->outBuffSize < ZSTD_compressBound(zcs->blockSize)+1) {
size_t const outBuffSize = ZSTD_compressBound(zcs->blockSize)+1;
zcs->outBuffSize = 0;
ZSTD_free(zcs->outBuff, zcs->customMem);
zcs->outBuff = (char*) ZSTD_malloc(outBuffSize, zcs->customMem);
zcs->outBuff = (char*)ZSTD_malloc(outBuffSize, zcs->customMem);
if (zcs->outBuff == NULL) return ERROR(memory_allocation);
zcs->outBuffSize = outBuffSize;
}

8
lib/zstd.h
View File

@ -460,8 +460,10 @@ ZSTDLIB_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t
***************************************/
/*! ZSTD_estimateCCtxSize() :
* Gives the amount of memory allocated for a ZSTD_CCtx given a set of compression parameters.
* `frameContentSize` is an optional parameter, provide `0` if unknown */
ZSTDLIB_API size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams);
* Set streaming to 1 if the CCtx will be used for streaming (CStream)
* Note : this function is currently unable to estimate additional memory allocation needed to create an internal CDict
* which can only happen when starting with ZSTD_initCStream_usingDict() */
ZSTDLIB_API size_t ZSTD_estimateCCtxSize(ZSTD_compressionParameters cParams, unsigned streaming);
/*! ZSTD_createCCtx_advanced() :
* Create a ZSTD compression context using external alloc and free functions */
@ -599,7 +601,7 @@ ZSTDLIB_API unsigned ZSTD_getDictID_fromFrame(const void* src, size_t srcSize);
ZSTDLIB_API ZSTD_CStream* ZSTD_createCStream_advanced(ZSTD_customMem customMem);
ZSTDLIB_API size_t ZSTD_sizeof_CStream(const ZSTD_CStream* zcs); /**< same as ZSTD_sizeof_CCtx */
ZSTDLIB_API size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize); /**< pledgedSrcSize must be correct, a size of 0 means unknown. for a frame size of 0 use initCStream_advanced */
ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); /**< note: a dict will not be used if dict == NULL or dictSize < 8 */
ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); /**< note: a dict will not be used if dict == NULL or dictSize < 8. This result in the creation of an internal CDict */
ZSTDLIB_API size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize,
ZSTD_parameters params, unsigned long long pledgedSrcSize); /**< pledgedSrcSize is optional and can be 0 (meaning unknown). note: if the contentSizeFlag is set, pledgedSrcSize == 0 means the source size is actually 0 */
ZSTDLIB_API size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict); /**< note : cdict will just be referenced, and must outlive compression session */

4
tests/paramgrill.c
View File

@ -388,8 +388,8 @@ static int BMK_seed(winnerInfo_t* winners, const ZSTD_compressionParameters para
double W_DMemUsed_note = W_ratioNote * ( 40 + 9*cLevel) - log((double)W_DMemUsed);
double O_DMemUsed_note = O_ratioNote * ( 40 + 9*cLevel) - log((double)O_DMemUsed);
size_t W_CMemUsed = (1 << params.windowLog) + ZSTD_estimateCCtxSize(params);
size_t O_CMemUsed = (1 << winners[cLevel].params.windowLog) + ZSTD_estimateCCtxSize(winners[cLevel].params);
size_t W_CMemUsed = (1 << params.windowLog) + ZSTD_estimateCCtxSize(params, 0/*streaming*/);
size_t O_CMemUsed = (1 << winners[cLevel].params.windowLog) + ZSTD_estimateCCtxSize(winners[cLevel].params, 0);
double W_CMemUsed_note = W_ratioNote * ( 50 + 13*cLevel) - log((double)W_CMemUsed);
double O_CMemUsed_note = O_ratioNote * ( 50 + 13*cLevel) - log((double)O_CMemUsed);