</b>/* multi-threading parameters */<b>
</b>/* These parameters are only useful if multi-threading is enabled (ZSTD_MULTITHREAD).<b>
* They return an error otherwise. */
- ZSTD_p_nbThreads=400, </b>/* Select how many threads a compression job can spawn (default:1)<b>
- * More threads improve speed, but also increase memory usage.
- * Can only receive a value > 1 if ZSTD_MULTITHREAD is enabled.
- * Special: value 0 means "do not change nbThreads" */
- ZSTD_p_nonBlockingMode, </b>/* Single thread mode is by default "blocking" :<b>
- * it finishes its job as much as possible, and only then gives back control to caller.
- * In contrast, multi-thread is by default "non-blocking" :
- * it takes some input, flush some output if available, and immediately gives back control to caller.
- * Compression work is performed in parallel, within worker threads.
- * (note : a strong exception to this rule is when first job is called with ZSTD_e_end : it becomes blocking)
- * Setting this parameter to 1 will enforce non-blocking mode even when only 1 thread is selected.
- * It allows the caller to do other tasks while the worker thread compresses in parallel. */
+ ZSTD_p_nbWorkers=400, </b>/* Select how many threads will be spawned to compress in parallel.<b>
- * Triggers asynchronous mode, even with nbWorkers = 1.
- * Can only be set to a value >= 1 if ZSTD_MULTITHREAD is enabled.
- * More threads improve speed, but also increase memory usage.
- * Default value is `0`, aka "blocking mode" : no worker is spawned, compression is performed inside Caller's thread */
++ * When nbWorkers >= 1, triggers asynchronous mode :
++ * ZSTD_compress_generic() consumes some input, flush some output if possible, and immediately gives back control to caller,
++ * while compression work is performed in parallel, within worker threads.
++ * (note : a strong exception to this rule is when first invocation sets ZSTD_e_end : it becomes a blocking call).
++ * More workers improve speed, but also increase memory usage.
++ * Default value is `0`, aka "single-threaded mode" : no worker is spawned, compression is performed inside Caller's thread, all invocations are blocking */
ZSTD_p_jobSize, </b>/* Size of a compression job. This value is only enforced in streaming (non-blocking) mode.<b>
* Each compression job is completed in parallel, so indirectly controls the nb of active threads.
* 0 means default, which is dynamically determined based on compression parameters.
</b></pre><BR>
<pre><b>size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned value);
</b><p> Set one compression parameter, selected by enum ZSTD_cParameter.
++ Setting a parameter is generally only possible during frame initialization (before starting compression),
++ except for a few exceptions which can be updated during compression: compressionLevel, hashLog, chainLog, searchLog, minMatch, targetLength and strategy.
Note : when `value` is an enum, cast it to unsigned for proper type checking.
-- @result : informational value (typically, the one being set, possibly corrected),
++ @result : informational value (typically, value being set clamped correctly),
or an error code (which can be tested with ZSTD_isError()).
</p></pre><BR>
<pre><b>size_t ZSTD_CCtx_setParametersUsingCCtxParams(
ZSTD_CCtx* cctx, const ZSTD_CCtx_params* params);
</b><p> Apply a set of ZSTD_CCtx_params to the compression context.
-- This must be done before the dictionary is loaded.
-- The pledgedSrcSize is treated as unknown.
- Multithreading parameters are applied only if nbWorkers >= 1.
- Multithreading parameters are applied only if nbThreads > 1.
++ This can be done even after compression is started,
++ if nbWorkers==0, this will have no impact until a new compression is started.
++ if nbWorkers>=1, new parameters will be picked up at next job,
++ with a few restrictions (windowLog, pledgedSrcSize, nbWorkers, jobSize, and overlapLog are not updated).
</p></pre><BR>
/*-*************************************
* Constants
***************************************/
-static const U32 g_searchStrength = 8;
-#define HASH_READ_SIZE 8
+#define kSearchStrength 8
+#define HASH_READ_SIZE 8
+#define ZSTD_CLEVEL_CUSTOM 999
+ #define ZSTD_DUBT_UNSORTED_MARK 1 /* For btlazy2 strategy, index 1 now means "unsorted".
+ It could be confused for a real successor at index "1", if sorted as larger than its predecessor.
+ It's not a big deal though : candidate will just be sorted again.
+ Additionnally, candidate position 1 will be lost.
+ But candidate 1 cannot hide a large tree of candidates, so it's a minimal loss.
+ The benefit is that ZSTD_DUBT_UNSORTED_MARK cannot be misdhandled after table re-use with a different strategy */
/*-*************************************
projects / thirdparty / zstd.git / commitdiff
