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Romain Hardouin commented on CASSANDRA-15296: --------------------------------------------- TLDR: the compression level interval is {{[-(2<<17), 22]}} i.e. {{[-131072, 22]}} Looking at Z Standard C sources, the maximum is indeed 22, not 2 (it's a typo): {code:c} #define ZSTD_MAX_CLEVEL 22 int ZSTD_maxCLevel(void) { return ZSTD_MAX_CLEVEL; } int ZSTD_minCLevel(void) { return (int)-ZSTD_TARGETLENGTH_MAX; } {code} [https://github.com/facebook/zstd/blob/519834738228cc810b48a2d44ff295b845842af4/lib/compress/zstd_compress.c#L3823] {{ZSTD_TARGETLENGTH_MAX}} is defined as: {code:c} #define ZSTD_TARGETLENGTH_MAX ZSTD_BLOCKSIZE_MAX {code} {code:c} #define ZSTD_BLOCKSIZELOG_MAX 17 #define ZSTD_BLOCKSIZE_MAX (1<<ZSTD_BLOCKSIZELOG_MAX) {code} > ZstdCompressor compression_level setting > ---------------------------------------- > > Key: CASSANDRA-15296 > URL: https://issues.apache.org/jira/browse/CASSANDRA-15296 > Project: Cassandra > Issue Type: Bug > Components: Dependencies, Feature/Compression > Reporter: DeepakVohra > Priority: Normal > > The DEFAULT_COMPRESSION_LEVEL for ZstdCompressor is set to 3, but its range > for compression_level is indicated to be between -131072 and 2. The default > value is outside the range. Is it by design or a bug? > {code:java} > - ``compression_level`` is only applicable for ``ZstdCompressor`` and accepts > values between ``-131072`` and ``2``. > // Compressor Defaults > public static final int DEFAULT_COMPRESSION_LEVEL = 3; > {code} > https://github.com/apache/cassandra/commit/dccf53061a61e7c632669c60cd94626e405518e9 -- This message was sent by Atlassian Jira (v8.3.2#803003) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org