From d85bdf8e430a92ce54a8a71b83b233d724f8620e Mon Sep 17 00:00:00 2001 From: Justin Pryzby Date: Fri, 12 Mar 2021 14:32:10 -0600 Subject: [PATCH v7 5/9] (re)add wal_compression_method: lz4 --- doc/src/sgml/config.sgml | 3 ++- doc/src/sgml/install-windows.sgml | 2 +- doc/src/sgml/installation.sgml | 5 +++-- src/backend/access/transam/xlog.c | 3 +++ src/backend/access/transam/xloginsert.c | 17 ++++++++++++++++- src/backend/access/transam/xlogreader.c | 12 ++++++++++++ src/backend/utils/misc/postgresql.conf.sample | 2 +- src/include/access/xlog_internal.h | 1 + 8 files changed, 39 insertions(+), 6 deletions(-) diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 70effa6345..f2209f5df0 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -3147,7 +3147,8 @@ include_dir 'conf.d' This parameter selects the compression method used to compress WAL when wal_compression is enabled. - The supported methods are pglz and zlib. + The supported methods are pglz, zlib, and (if configured when + PostgreSQL was built) lz4. The default value is pglz. Only superusers can change this setting. diff --git a/doc/src/sgml/install-windows.sgml b/doc/src/sgml/install-windows.sgml index db53ee85a8..a023584722 100644 --- a/doc/src/sgml/install-windows.sgml +++ b/doc/src/sgml/install-windows.sgml @@ -299,7 +299,7 @@ $ENV{MSBFLAGS}="/m"; LZ4 Required for supporting LZ4 compression - method for compressing the table data. Binaries and source can be + method for compressing table or WAL data. Binaries and source can be downloaded from . diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml index 3c0aa118c7..7c8cdac25a 100644 --- a/doc/src/sgml/installation.sgml +++ b/doc/src/sgml/installation.sgml @@ -270,7 +270,8 @@ su - postgres You need LZ4, if you want to support compression of data with this method; see - . + and + . @@ -980,7 +981,7 @@ build-postgresql: Build with LZ4 compression support. This allows the use of LZ4 for - compression of table data. + compression of table and WAL data. diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index a43e04fc0b..999896487e 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -186,6 +186,9 @@ const struct config_enum_entry wal_compression_options[] = { {"pglz", WAL_COMPRESSION_PGLZ, false}, #ifdef HAVE_LIBZ {"zlib", WAL_COMPRESSION_ZLIB, false}, +#endif +#ifdef USE_LZ4 + {"lz4", WAL_COMPRESSION_LZ4, false}, #endif {NULL, 0, false} }; diff --git a/src/backend/access/transam/xloginsert.c b/src/backend/access/transam/xloginsert.c index 5ab07621d6..30804e8cd5 100644 --- a/src/backend/access/transam/xloginsert.c +++ b/src/backend/access/transam/xloginsert.c @@ -41,10 +41,17 @@ #define ZLIB_MAX_BLCKSZ 0 #endif +#ifdef USE_LZ4 +#include "lz4.h" +#define LZ4_MAX_BLCKSZ LZ4_COMPRESSBOUND(BLCKSZ) +#else +#define LZ4_MAX_BLCKSZ 0 +#endif + /* Buffer size required to store a compressed version of backup block image */ #define PGLZ_MAX_BLCKSZ PGLZ_MAX_OUTPUT(BLCKSZ) -#define COMPRESS_BUFSIZE Max(PGLZ_MAX_BLCKSZ, ZLIB_MAX_BLCKSZ) +#define COMPRESS_BUFSIZE Max(Max(PGLZ_MAX_BLCKSZ, ZLIB_MAX_BLCKSZ), LZ4_MAX_BLCKSZ) /* * For each block reference registered with XLogRegisterBuffer, we fill in @@ -891,6 +898,14 @@ XLogCompressBackupBlock(char *page, uint16 hole_offset, uint16 hole_length, } #endif +#ifdef USE_LZ4 + case WAL_COMPRESSION_LZ4: + len = LZ4_compress_fast(source, dest, orig_len, COMPRESS_BUFSIZE, 1); + if (len == 0) + len = -1; + break; +#endif + default: /* * It should be impossible to get here for unsupported algorithms, diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c index 0d8830fc50..97165f1bb1 100644 --- a/src/backend/access/transam/xlogreader.c +++ b/src/backend/access/transam/xlogreader.c @@ -37,6 +37,10 @@ #include #endif +#ifdef USE_LZ4 +#include "lz4.h" +#endif + static void report_invalid_record(XLogReaderState *state, const char *fmt,...) pg_attribute_printf(2, 3); static bool allocate_recordbuf(XLogReaderState *state, uint32 reclength); @@ -1544,6 +1548,7 @@ XLogRecGetBlockData(XLogReaderState *record, uint8 block_id, Size *len) struct walcompression walmethods[] = { {"pglz", WAL_COMPRESSION_PGLZ}, {"zlib", WAL_COMPRESSION_ZLIB}, + {"lz4", WAL_COMPRESSION_LZ4}, }; /* @@ -1609,6 +1614,13 @@ RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page) } #endif +#ifdef USE_LZ4 + case WAL_COMPRESSION_LZ4: + decomp_result = LZ4_decompress_safe(ptr, tmp.data, + bkpb->bimg_len, BLCKSZ-bkpb->hole_length); + break; +#endif + default: report_invalid_record(record, "image at %X/%X is compressed with unsupported codec, block %d (%d/%s)", (uint32) (record->ReadRecPtr >> 32), diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index baed4d9228..6421ddbde8 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -219,7 +219,7 @@ #wal_log_hints = off # also do full page writes of non-critical updates # (change requires restart) #wal_compression = off # enable compression of full-page writes -#wal_compression_method = pglz # pglz, zlib +#wal_compression_method = pglz # pglz, zlib, lz4 #wal_init_zero = on # zero-fill new WAL files #wal_recycle = on # recycle WAL files #wal_buffers = -1 # min 32kB, -1 sets based on shared_buffers diff --git a/src/include/access/xlog_internal.h b/src/include/access/xlog_internal.h index ceca0f7189..fc57ea728e 100644 --- a/src/include/access/xlog_internal.h +++ b/src/include/access/xlog_internal.h @@ -336,6 +336,7 @@ typedef enum WalCompression { WAL_COMPRESSION_PGLZ, WAL_COMPRESSION_ZLIB, + WAL_COMPRESSION_LZ4, } WalCompression; extern const char *wal_compression_name(WalCompression compression); -- 2.17.0