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Perf improvements

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try decay
strategy selection skipping
This commit is contained in:
George Lu
2018-07-26 16:45:00 -07:00
parent 2bdfe6ca71
commit 3a2e95eba4
1 changed files with 10 additions and 2 deletions
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12
tests/paramgrill.c
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@@ -2079,7 +2079,9 @@ static ZSTD_compressionParameters maskParams(ZSTD_compressionParameters base, ZS
return base; return base;
} }
/* experiment with playing with this and decay value */
#define MAX_TRIES 8 #define MAX_TRIES 8
#define TRY_DECAY 3
/* main fn called when using --optimize */ /* main fn called when using --optimize */
/* Does strategy selection by benchmarking default compression levels /* Does strategy selection by benchmarking default compression levels
* then optimizes by strategy, starting with the best one and moving * then optimizes by strategy, starting with the best one and moving
@@ -2092,6 +2094,7 @@ static ZSTD_compressionParameters maskParams(ZSTD_compressionParameters base, ZS
* paramTarget - parameter constraints (i.e. restriction search space to where strategy = ZSTD_fast) * paramTarget - parameter constraints (i.e. restriction search space to where strategy = ZSTD_fast)
* cLevel - compression level to exceed (all solutions must be > lvl in cSpeed + ratio) * cLevel - compression level to exceed (all solutions must be > lvl in cSpeed + ratio)
*/ */
static int optimizeForSize(const char* const * const fileNamesTable, const size_t nbFiles, const char* dictFileName, constraint_t target, ZSTD_compressionParameters paramTarget, int cLevel) static int optimizeForSize(const char* const * const fileNamesTable, const size_t nbFiles, const char* dictFileName, constraint_t target, ZSTD_compressionParameters paramTarget, int cLevel)
{ {
varInds_t varArray [NUM_PARAMS]; varInds_t varArray [NUM_PARAMS];
@@ -2202,7 +2205,7 @@ static int optimizeForSize(const char* const * const fileNamesTable, const size_
/* strategy selection */ /* strategy selection */
const int maxSeeds = g_noSeed ? 1 : ZSTD_maxCLevel(); const int maxSeeds = g_noSeed ? 1 : ZSTD_maxCLevel();
DEBUGOUTPUT("Strategy Selection\n"); DEBUGOUTPUT("Strategy Selection\n");
if(paramTarget.strategy == 0) { /* no variable based constraints */ if(paramTarget.strategy == 0) {
BMK_result_t candidate; BMK_result_t candidate;
int i; int i;
for (i=1; i<=maxSeeds; i++) { for (i=1; i<=maxSeeds; i++) {
@@ -2216,6 +2219,11 @@ static int optimizeForSize(const char* const * const fileNamesTable, const size_
winner.result = candidate; winner.result = candidate;
winner.params = CParams; winner.params = CParams;
} }
/* if the current params are too slow, just stop. */
if(target.cSpeed != 0 && target.cSpeed > winner.result.cSpeed / 2) {
break;
}
} }
} }
} }
@@ -2248,7 +2256,7 @@ static int optimizeForSize(const char* const * const fileNamesTable, const size_
} }
st = nextStrategy(st, bestStrategy); st = nextStrategy(st, bestStrategy);
tries--; tries -= TRY_DECAY;
} }
} else { } else {
winner = optimizeFixedStrategy(buf, ctx, target, paramTarget, paramTarget.strategy, winner = optimizeFixedStrategy(buf, ctx, target, paramTarget, paramTarget.strategy,