From 049b5964e4c3b5add51b02b5a74732df7af72beb Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 26 Jan 2024 11:25:26 -0500 Subject: [PATCH v11 2/6] In dumps, group large objects into matching metadata and data entries. Commit c0d5be5d6 caused pg_dump to create a separate BLOB metadata TOC entry for each large object (blob), but it did not touch the ancient decision to put all the blobs' data into a single BLOBS TOC entry. This is bad for a few reasons: for databases with millions of blobs, the TOC becomes unreasonably large, causing performance issues; selective restore of just some blobs is quite impossible; and we cannot parallelize either dump or restore of the blob data, since our architecture for that relies on farming out whole TOC entries to worker processes. To improve matters, let's group multiple blobs into each blob metadata TOC entry, and then make corresponding per-group blob data TOC entries. Selective restore using pg_restore's -l/-L switches is then possible, though only at the group level. (Perhaps we should provide a switch to allow forcing one-blob-per-group for users who need precise selective restore and don't have huge numbers of blobs. This patch doesn't yet do that, instead just hard-wiring the maximum number of blobs per entry at 1000.) The blobs in a group must all have the same owner, since the TOC entry format only allows one owner to be named. In this implementation we also require them to all share the same ACL (grants); the archive format wouldn't require that, but pg_dump's representation of DumpableObjects does. It seems unlikely that either restriction will be problematic for databases with huge numbers of blobs. The metadata TOC entries now have a "desc" string of "BLOB METADATA", and their "defn" string is just a newline-separated list of blob OIDs. The restore code has to generate creation commands, ALTER OWNER commands, and drop commands (for --clean mode) from that. We would need special-case code for ALTER OWNER and drop in any case, so the alternative of keeping the "defn" as directly executable SQL code for creation wouldn't buy much, and it seems like it'd bloat the archive to little purpose. The data TOC entries ("BLOBS") can be exactly the same as before, except that now there can be more than one, so we'd better give them identifying tag strings. We have to bump the archive file format version number, since existing versions of pg_restore wouldn't know they need to do something special for BLOB METADATA, plus they aren't going to work correctly with multiple BLOBS entries. Also, the directory and tar-file format handlers need some work for multiple BLOBS entries: they used to hard-wire the file name as "blobs.toc", which is replaced here with "blobs_.toc". The 002_pg_dump.pl test script also knows about that and requires minor updates. (I had to drop the test for manually-compressed blobs.toc files with LZ4, because lz4's obtuse command line design requires explicit specification of the output file name which seems impractical here. I don't think we're losing any useful test coverage thereby; that test stanza seems completely duplicative with the gzip and zstd cases anyway.) As this stands, we still generate a separate TOC entry for any comment, security label, or ACL attached to a blob. I feel comfortable in believing that comments and security labels on blobs are rare; but we might have to do something about aggregating blob ACLs into grouped TOC entries to avoid blowing up the TOC size, if there are use cases with large numbers of non-default blob ACLs. That can be done later though, as it would not create any compatibility issues. --- src/bin/pg_dump/common.c | 26 +++ src/bin/pg_dump/pg_backup_archiver.c | 76 +++++-- src/bin/pg_dump/pg_backup_archiver.h | 6 +- src/bin/pg_dump/pg_backup_custom.c | 4 +- src/bin/pg_dump/pg_backup_db.c | 27 +++ src/bin/pg_dump/pg_backup_directory.c | 38 ++-- src/bin/pg_dump/pg_backup_null.c | 4 +- src/bin/pg_dump/pg_backup_tar.c | 39 +++- src/bin/pg_dump/pg_dump.c | 287 +++++++++++++++----------- src/bin/pg_dump/pg_dump.h | 11 + src/bin/pg_dump/t/002_pg_dump.pl | 30 ++- 11 files changed, 361 insertions(+), 187 deletions(-) diff --git a/src/bin/pg_dump/common.c b/src/bin/pg_dump/common.c index 0ed18b72d6..c7dd0b11fd 100644 --- a/src/bin/pg_dump/common.c +++ b/src/bin/pg_dump/common.c @@ -47,6 +47,8 @@ static DumpId lastDumpId = 0; /* Note: 0 is InvalidDumpId */ * expects that it can move them around when resizing the table. So we * cannot make the DumpableObjects be elements of the hash table directly; * instead, the hash table elements contain pointers to DumpableObjects. + * This does have the advantage of letting us map multiple CatalogIds + * to one DumpableObject, which is useful for blobs. * * It turns out to be convenient to also use this data structure to map * CatalogIds to owning extensions, if any. Since extension membership @@ -700,6 +702,30 @@ AssignDumpId(DumpableObject *dobj) } } +/* + * recordAdditionalCatalogID + * Record an additional catalog ID for the given DumpableObject + */ +void +recordAdditionalCatalogID(CatalogId catId, DumpableObject *dobj) +{ + CatalogIdMapEntry *entry; + bool found; + + /* CatalogId hash table must exist, if we have a DumpableObject */ + Assert(catalogIdHash != NULL); + + /* Add reference to CatalogId hash */ + entry = catalogid_insert(catalogIdHash, catId, &found); + if (!found) + { + entry->dobj = NULL; + entry->ext = NULL; + } + Assert(entry->dobj == NULL); + entry->dobj = dobj; +} + /* * Assign a DumpId that's not tied to a DumpableObject. * diff --git a/src/bin/pg_dump/pg_backup_archiver.c b/src/bin/pg_dump/pg_backup_archiver.c index f5935b08bb..aabcd8dde3 100644 --- a/src/bin/pg_dump/pg_backup_archiver.c +++ b/src/bin/pg_dump/pg_backup_archiver.c @@ -512,7 +512,20 @@ RestoreArchive(Archive *AHX) * don't necessarily emit it verbatim; at this point we add an * appropriate IF EXISTS clause, if the user requested it. */ - if (*te->dropStmt != '\0') + if (strcmp(te->desc, "BLOB METADATA") == 0) + { + /* We must generate the per-blob commands */ + if (ropt->if_exists) + IssueCommandPerBlob(AH, te, + "SELECT pg_catalog.lo_unlink(oid) " + "FROM pg_catalog.pg_largeobject_metadata " + "WHERE oid = '", "'"); + else + IssueCommandPerBlob(AH, te, + "SELECT pg_catalog.lo_unlink('", + "')"); + } + else if (*te->dropStmt != '\0') { if (!ropt->if_exists || strncmp(te->dropStmt, "--", 2) == 0) @@ -528,12 +541,12 @@ RestoreArchive(Archive *AHX) { /* * Inject an appropriate spelling of "if exists". For - * large objects, we have a separate routine that + * old-style large objects, we have a routine that * knows how to do it, without depending on * te->dropStmt; use that. For other objects we need * to parse the command. */ - if (strncmp(te->desc, "BLOB", 4) == 0) + if (strcmp(te->desc, "BLOB") == 0) { DropLOIfExists(AH, te->catalogId.oid); } @@ -1290,7 +1303,7 @@ EndLO(Archive *AHX, Oid oid) **********/ /* - * Called by a format handler before any LOs are restored + * Called by a format handler before a group of LOs is restored */ void StartRestoreLOs(ArchiveHandle *AH) @@ -1309,7 +1322,7 @@ StartRestoreLOs(ArchiveHandle *AH) } /* - * Called by a format handler after all LOs are restored + * Called by a format handler after a group of LOs is restored */ void EndRestoreLOs(ArchiveHandle *AH) @@ -2994,13 +3007,14 @@ _tocEntryRequired(TocEntry *te, teSection curSection, ArchiveHandle *AH) { /* * Special Case: If 'SEQUENCE SET' or anything to do with LOs, then it - * is considered a data entry. We don't need to check for the BLOBS - * entry or old-style BLOB COMMENTS, because they will have hadDumper - * = true ... but we do need to check new-style BLOB ACLs, comments, + * is considered a data entry. We don't need to check for BLOBS or + * old-style BLOB COMMENTS entries, because they will have hadDumper = + * true ... but we do need to check new-style BLOB ACLs, comments, * etc. */ if (strcmp(te->desc, "SEQUENCE SET") == 0 || strcmp(te->desc, "BLOB") == 0 || + strcmp(te->desc, "BLOB METADATA") == 0 || (strcmp(te->desc, "ACL") == 0 && strncmp(te->tag, "LARGE OBJECT ", 13) == 0) || (strcmp(te->desc, "COMMENT") == 0 && @@ -3041,6 +3055,7 @@ _tocEntryRequired(TocEntry *te, teSection curSection, ArchiveHandle *AH) if (!(ropt->sequence_data && strcmp(te->desc, "SEQUENCE SET") == 0) && !(ropt->binary_upgrade && (strcmp(te->desc, "BLOB") == 0 || + strcmp(te->desc, "BLOB METADATA") == 0 || (strcmp(te->desc, "ACL") == 0 && strncmp(te->tag, "LARGE OBJECT ", 13) == 0) || (strcmp(te->desc, "COMMENT") == 0 && @@ -3613,18 +3628,26 @@ _printTocEntry(ArchiveHandle *AH, TocEntry *te, bool isData) } /* - * Actually print the definition. + * Actually print the definition. Normally we can just print the defn + * string if any, but we have two special cases: * - * Really crude hack for suppressing AUTHORIZATION clause that old pg_dump + * 1. A crude hack for suppressing AUTHORIZATION clause that old pg_dump * versions put into CREATE SCHEMA. Don't mutate the variant for schema * "public" that is a comment. We have to do this when --no-owner mode is * selected. This is ugly, but I see no other good way ... + * + * 2. BLOB METADATA entries need special processing since their defn + * strings are just lists of OIDs, not complete SQL commands. */ if (ropt->noOwner && strcmp(te->desc, "SCHEMA") == 0 && strncmp(te->defn, "--", 2) != 0) { ahprintf(AH, "CREATE SCHEMA %s;\n\n\n", fmtId(te->tag)); } + else if (strcmp(te->desc, "BLOB METADATA") == 0) + { + IssueCommandPerBlob(AH, te, "SELECT pg_catalog.lo_create('", "')"); + } else { if (te->defn && strlen(te->defn) > 0) @@ -3645,18 +3668,31 @@ _printTocEntry(ArchiveHandle *AH, TocEntry *te, bool isData) te->owner && strlen(te->owner) > 0 && te->dropStmt && strlen(te->dropStmt) > 0) { - PQExpBufferData temp; + if (strcmp(te->desc, "BLOB METADATA") == 0) + { + /* BLOB METADATA needs special code to handle multiple LOs */ + char *cmdEnd = psprintf(" OWNER TO %s", fmtId(te->owner)); + + IssueCommandPerBlob(AH, te, "ALTER LARGE OBJECT ", cmdEnd); + pg_free(cmdEnd); + } + else + { + /* For all other cases, we can use _getObjectDescription */ + PQExpBufferData temp; - initPQExpBuffer(&temp); - _getObjectDescription(&temp, te); + initPQExpBuffer(&temp); + _getObjectDescription(&temp, te); - /* - * If _getObjectDescription() didn't fill the buffer, then there is no - * owner. - */ - if (temp.data[0]) - ahprintf(AH, "ALTER %s OWNER TO %s;\n\n", temp.data, fmtId(te->owner)); - termPQExpBuffer(&temp); + /* + * If _getObjectDescription() didn't fill the buffer, then there + * is no owner. + */ + if (temp.data[0]) + ahprintf(AH, "ALTER %s OWNER TO %s;\n\n", + temp.data, fmtId(te->owner)); + termPQExpBuffer(&temp); + } } /* diff --git a/src/bin/pg_dump/pg_backup_archiver.h b/src/bin/pg_dump/pg_backup_archiver.h index 917283fd34..e4dd395582 100644 --- a/src/bin/pg_dump/pg_backup_archiver.h +++ b/src/bin/pg_dump/pg_backup_archiver.h @@ -68,10 +68,12 @@ #define K_VERS_1_15 MAKE_ARCHIVE_VERSION(1, 15, 0) /* add * compression_algorithm * in header */ +#define K_VERS_1_16 MAKE_ARCHIVE_VERSION(1, 16, 0) /* BLOB METADATA entries + * and multiple BLOBS */ /* Current archive version number (the format we can output) */ #define K_VERS_MAJOR 1 -#define K_VERS_MINOR 15 +#define K_VERS_MINOR 16 #define K_VERS_REV 0 #define K_VERS_SELF MAKE_ARCHIVE_VERSION(K_VERS_MAJOR, K_VERS_MINOR, K_VERS_REV) @@ -448,6 +450,8 @@ extern void InitArchiveFmt_Tar(ArchiveHandle *AH); extern bool isValidTarHeader(char *header); extern void ReconnectToServer(ArchiveHandle *AH, const char *dbname); +extern void IssueCommandPerBlob(ArchiveHandle *AH, TocEntry *te, + const char *cmdBegin, const char *cmdEnd); extern void DropLOIfExists(ArchiveHandle *AH, Oid oid); void ahwrite(const void *ptr, size_t size, size_t nmemb, ArchiveHandle *AH); diff --git a/src/bin/pg_dump/pg_backup_custom.c b/src/bin/pg_dump/pg_backup_custom.c index 7c6ac89dd4..55107b2005 100644 --- a/src/bin/pg_dump/pg_backup_custom.c +++ b/src/bin/pg_dump/pg_backup_custom.c @@ -338,7 +338,7 @@ _EndData(ArchiveHandle *AH, TocEntry *te) } /* - * Called by the archiver when starting to save all BLOB DATA (not schema). + * Called by the archiver when starting to save BLOB DATA (not schema). * This routine should save whatever format-specific information is needed * to read the LOs back into memory. * @@ -398,7 +398,7 @@ _EndLO(ArchiveHandle *AH, TocEntry *te, Oid oid) } /* - * Called by the archiver when finishing saving all BLOB DATA. + * Called by the archiver when finishing saving BLOB DATA. * * Optional. */ diff --git a/src/bin/pg_dump/pg_backup_db.c b/src/bin/pg_dump/pg_backup_db.c index b297ca049d..c14d813b21 100644 --- a/src/bin/pg_dump/pg_backup_db.c +++ b/src/bin/pg_dump/pg_backup_db.c @@ -541,6 +541,33 @@ CommitTransaction(Archive *AHX) ExecuteSqlCommand(AH, "COMMIT", "could not commit database transaction"); } +/* + * Issue per-blob commands for the large object(s) listed in the TocEntry + * + * The TocEntry's defn string is assumed to consist of large object OIDs, + * one per line. Wrap these in the given SQL command fragments and issue + * the commands. (cmdEnd need not include a semicolon.) + */ +void +IssueCommandPerBlob(ArchiveHandle *AH, TocEntry *te, + const char *cmdBegin, const char *cmdEnd) +{ + /* Make a writable copy of the command string */ + char *buf = pg_strdup(te->defn); + char *st; + char *en; + + st = buf; + while ((en = strchr(st, '\n')) != NULL) + { + *en++ = '\0'; + ahprintf(AH, "%s%s%s;\n", cmdBegin, st, cmdEnd); + st = en; + } + ahprintf(AH, "\n"); + pg_free(buf); +} + void DropLOIfExists(ArchiveHandle *AH, Oid oid) { diff --git a/src/bin/pg_dump/pg_backup_directory.c b/src/bin/pg_dump/pg_backup_directory.c index de3cfea02e..7be8d5487d 100644 --- a/src/bin/pg_dump/pg_backup_directory.c +++ b/src/bin/pg_dump/pg_backup_directory.c @@ -5,8 +5,10 @@ * A directory format dump is a directory, which contains a "toc.dat" file * for the TOC, and a separate file for each data entry, named ".dat". * Large objects are stored in separate files named "blob_.dat", - * and there's a plain-text TOC file for them called "blobs.toc". If - * compression is used, each data file is individually compressed and the + * and there's a plain-text TOC file for each BLOBS TOC entry named + * "blobs_.toc" (or just "blobs.toc" in archive versions before 16). + * + * If compression is used, each data file is individually compressed and the * ".gz" suffix is added to the filenames. The TOC files are never * compressed by pg_dump, however they are accepted with the .gz suffix too, * in case the user has manually compressed them with 'gzip'. @@ -51,7 +53,7 @@ typedef struct char *directory; CompressFileHandle *dataFH; /* currently open data file */ - CompressFileHandle *LOsTocFH; /* file handle for blobs.toc */ + CompressFileHandle *LOsTocFH; /* file handle for blobs_NNN.toc */ ParallelState *pstate; /* for parallel backup / restore */ } lclContext; @@ -81,7 +83,7 @@ static void _StartLOs(ArchiveHandle *AH, TocEntry *te); static void _StartLO(ArchiveHandle *AH, TocEntry *te, Oid oid); static void _EndLO(ArchiveHandle *AH, TocEntry *te, Oid oid); static void _EndLOs(ArchiveHandle *AH, TocEntry *te); -static void _LoadLOs(ArchiveHandle *AH); +static void _LoadLOs(ArchiveHandle *AH, TocEntry *te); static void _PrepParallelRestore(ArchiveHandle *AH); static void _Clone(ArchiveHandle *AH); @@ -232,7 +234,10 @@ _ArchiveEntry(ArchiveHandle *AH, TocEntry *te) tctx = (lclTocEntry *) pg_malloc0(sizeof(lclTocEntry)); if (strcmp(te->desc, "BLOBS") == 0) - tctx->filename = pg_strdup("blobs.toc"); + { + snprintf(fn, MAXPGPATH, "blobs_%d.toc", te->dumpId); + tctx->filename = pg_strdup(fn); + } else if (te->dataDumper) { snprintf(fn, MAXPGPATH, "%d.dat", te->dumpId); @@ -415,7 +420,7 @@ _PrintTocData(ArchiveHandle *AH, TocEntry *te) return; if (strcmp(te->desc, "BLOBS") == 0) - _LoadLOs(AH); + _LoadLOs(AH, te); else { char fname[MAXPGPATH]; @@ -426,17 +431,23 @@ _PrintTocData(ArchiveHandle *AH, TocEntry *te) } static void -_LoadLOs(ArchiveHandle *AH) +_LoadLOs(ArchiveHandle *AH, TocEntry *te) { Oid oid; lclContext *ctx = (lclContext *) AH->formatData; + lclTocEntry *tctx = (lclTocEntry *) te->formatData; CompressFileHandle *CFH; char tocfname[MAXPGPATH]; char line[MAXPGPATH]; StartRestoreLOs(AH); - setFilePath(AH, tocfname, "blobs.toc"); + /* + * Note: before archive v16, there was always only one BLOBS TOC entry, + * now there can be multiple. We don't need to worry what version we are + * reading though, because tctx->filename should be correct either way. + */ + setFilePath(AH, tocfname, tctx->filename); CFH = ctx->LOsTocFH = InitDiscoverCompressFileHandle(tocfname, PG_BINARY_R); @@ -632,7 +643,7 @@ _ReopenArchive(ArchiveHandle *AH) */ /* - * Called by the archiver when starting to save all BLOB DATA (not schema). + * Called by the archiver when starting to save BLOB DATA (not schema). * It is called just prior to the dumper's DataDumper routine. * * We open the large object TOC file here, so that we can append a line to @@ -642,10 +653,11 @@ static void _StartLOs(ArchiveHandle *AH, TocEntry *te) { lclContext *ctx = (lclContext *) AH->formatData; + lclTocEntry *tctx = (lclTocEntry *) te->formatData; pg_compress_specification compression_spec = {0}; char fname[MAXPGPATH]; - setFilePath(AH, fname, "blobs.toc"); + setFilePath(AH, fname, tctx->filename); /* The LO TOC file is never compressed */ compression_spec.algorithm = PG_COMPRESSION_NONE; @@ -690,7 +702,7 @@ _EndLO(ArchiveHandle *AH, TocEntry *te, Oid oid) pg_fatal("could not close LO data file: %m"); ctx->dataFH = NULL; - /* register the LO in blobs.toc */ + /* register the LO in blobs_NNN.toc */ len = snprintf(buf, sizeof(buf), "%u blob_%u.dat\n", oid, oid); if (!CFH->write_func(buf, len, CFH)) { @@ -703,7 +715,7 @@ _EndLO(ArchiveHandle *AH, TocEntry *te, Oid oid) } /* - * Called by the archiver when finishing saving all BLOB DATA. + * Called by the archiver when finishing saving BLOB DATA. * * We close the LOs TOC file. */ @@ -795,7 +807,7 @@ _PrepParallelRestore(ArchiveHandle *AH) } /* - * If this is the BLOBS entry, what we stat'd was blobs.toc, which + * If this is a BLOBS entry, what we stat'd was blobs_NNN.toc, which * most likely is a lot smaller than the actual blob data. We don't * have a cheap way to estimate how much smaller, but fortunately it * doesn't matter too much as long as we get the LOs processed diff --git a/src/bin/pg_dump/pg_backup_null.c b/src/bin/pg_dump/pg_backup_null.c index 776f057770..a3257f4fc8 100644 --- a/src/bin/pg_dump/pg_backup_null.c +++ b/src/bin/pg_dump/pg_backup_null.c @@ -113,7 +113,7 @@ _EndData(ArchiveHandle *AH, TocEntry *te) } /* - * Called by the archiver when starting to save all BLOB DATA (not schema). + * Called by the archiver when starting to save BLOB DATA (not schema). * This routine should save whatever format-specific information is needed * to read the LOs back into memory. * @@ -170,7 +170,7 @@ _EndLO(ArchiveHandle *AH, TocEntry *te, Oid oid) } /* - * Called by the archiver when finishing saving all BLOB DATA. + * Called by the archiver when finishing saving BLOB DATA. * * Optional. */ diff --git a/src/bin/pg_dump/pg_backup_tar.c b/src/bin/pg_dump/pg_backup_tar.c index 4cb9707e63..41ee52b1d6 100644 --- a/src/bin/pg_dump/pg_backup_tar.c +++ b/src/bin/pg_dump/pg_backup_tar.c @@ -94,7 +94,7 @@ typedef struct char *filename; } lclTocEntry; -static void _LoadLOs(ArchiveHandle *AH); +static void _LoadLOs(ArchiveHandle *AH, TocEntry *te); static TAR_MEMBER *tarOpen(ArchiveHandle *AH, const char *filename, char mode); static void tarClose(ArchiveHandle *AH, TAR_MEMBER *th); @@ -634,13 +634,13 @@ _PrintTocData(ArchiveHandle *AH, TocEntry *te) } if (strcmp(te->desc, "BLOBS") == 0) - _LoadLOs(AH); + _LoadLOs(AH, te); else _PrintFileData(AH, tctx->filename); } static void -_LoadLOs(ArchiveHandle *AH) +_LoadLOs(ArchiveHandle *AH, TocEntry *te) { Oid oid; lclContext *ctx = (lclContext *) AH->formatData; @@ -651,7 +651,26 @@ _LoadLOs(ArchiveHandle *AH) StartRestoreLOs(AH); - th = tarOpen(AH, NULL, 'r'); /* Open next file */ + /* + * The blobs_NNN.toc or blobs.toc file is fairly useless to us because it + * will appear only after the associated blob_NNN.dat files. For archive + * versions >= 16 we can look at the BLOBS entry's te->tag to discover the + * OID of the first blob we want to restore, and then search forward to + * find the appropriate blob_.dat file. For older versions we rely + * on the knowledge that there was only one BLOBS entry and just search + * for the first blob_.dat file. Once we find the first blob file to + * restore, restore all blobs until we reach the blobs[_NNN].toc file. + */ + if (AH->version >= K_VERS_1_16) + { + /* We rely on atooid to not complain about nnnn..nnnn tags */ + oid = atooid(te->tag); + snprintf(buf, sizeof(buf), "blob_%u.dat", oid); + th = tarOpen(AH, buf, 'r'); /* Advance to first desired file */ + } + else + th = tarOpen(AH, NULL, 'r'); /* Open next file */ + while (th != NULL) { ctx->FH = th; @@ -681,9 +700,9 @@ _LoadLOs(ArchiveHandle *AH) /* * Once we have found the first LO, stop at the first non-LO entry - * (which will be 'blobs.toc'). This coding would eat all the - * rest of the archive if there are no LOs ... but this function - * shouldn't be called at all in that case. + * (which will be 'blobs[_NNN].toc'). This coding would eat all + * the rest of the archive if there are no LOs ... but this + * function shouldn't be called at all in that case. */ if (foundLO) break; @@ -847,7 +866,7 @@ _scriptOut(ArchiveHandle *AH, const void *buf, size_t len) */ /* - * Called by the archiver when starting to save all BLOB DATA (not schema). + * Called by the archiver when starting to save BLOB DATA (not schema). * This routine should save whatever format-specific information is needed * to read the LOs back into memory. * @@ -862,7 +881,7 @@ _StartLOs(ArchiveHandle *AH, TocEntry *te) lclContext *ctx = (lclContext *) AH->formatData; char fname[K_STD_BUF_SIZE]; - sprintf(fname, "blobs.toc"); + sprintf(fname, "blobs_%d.toc", te->dumpId); ctx->loToc = tarOpen(AH, fname, 'w'); } @@ -908,7 +927,7 @@ _EndLO(ArchiveHandle *AH, TocEntry *te, Oid oid) } /* - * Called by the archiver when finishing saving all BLOB DATA. + * Called by the archiver when finishing saving BLOB DATA. * * Optional. * diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c index 171e591696..369816daef 100644 --- a/src/bin/pg_dump/pg_dump.c +++ b/src/bin/pg_dump/pg_dump.c @@ -160,6 +160,13 @@ static int nseclabels = 0; */ #define DUMP_DEFAULT_ROWS_PER_INSERT 1 +/* + * Maximum number of large objects to group into a single ArchiveEntry. + * At some point we might want to make this user-controllable, but for now + * a hard-wired setting will suffice. + */ +#define MAX_BLOBS_PER_ARCHIVE_ENTRY 1000 + /* * Macro for producing quoted, schema-qualified name of a dumpable object. */ @@ -3592,11 +3599,10 @@ getLOs(Archive *fout) { DumpOptions *dopt = fout->dopt; PQExpBuffer loQry = createPQExpBuffer(); - LoInfo *loinfo; - DumpableObject *lodata; PGresult *res; int ntups; int i; + int n; int i_oid; int i_lomowner; int i_lomacl; @@ -3604,11 +3610,15 @@ getLOs(Archive *fout) pg_log_info("reading large objects"); - /* Fetch LO OIDs, and owner/ACL data */ + /* + * Fetch LO OIDs and owner/ACL data. Order the data so that all the blobs + * with the same owner/ACL appear together. + */ appendPQExpBufferStr(loQry, "SELECT oid, lomowner, lomacl, " "acldefault('L', lomowner) AS acldefault " - "FROM pg_largeobject_metadata"); + "FROM pg_largeobject_metadata " + "ORDER BY lomowner, lomacl::pg_catalog.text, oid"); res = ExecuteSqlQuery(fout, loQry->data, PGRES_TUPLES_OK); @@ -3620,30 +3630,72 @@ getLOs(Archive *fout) ntups = PQntuples(res); /* - * Each large object has its own "BLOB" archive entry. + * Group the blobs into suitably-sized groups that have the same owner and + * ACL setting, and build a metadata and a data DumpableObject for each + * group. (If we supported initprivs for blobs, we'd have to insist that + * groups also share initprivs settings, since the DumpableObject only has + * room for one.) i is the index of the first tuple in the current group, + * and n is the number of tuples we include in the group. */ - loinfo = (LoInfo *) pg_malloc(ntups * sizeof(LoInfo)); + for (i = 0; i < ntups; i += n) + { + Oid thisoid = atooid(PQgetvalue(res, i, i_oid)); + char *thisowner = PQgetvalue(res, i, i_lomowner); + char *thisacl = PQgetvalue(res, i, i_lomacl); + LoInfo *loinfo; + DumpableObject *lodata; + char namebuf[64]; + + /* Scan to find first tuple not to be included in group */ + n = 1; + while (n < MAX_BLOBS_PER_ARCHIVE_ENTRY && i + n < ntups) + { + if (strcmp(thisowner, PQgetvalue(res, i + n, i_lomowner)) != 0 || + strcmp(thisacl, PQgetvalue(res, i + n, i_lomacl)) != 0) + break; + n++; + } - for (i = 0; i < ntups; i++) - { - loinfo[i].dobj.objType = DO_LARGE_OBJECT; - loinfo[i].dobj.catId.tableoid = LargeObjectRelationId; - loinfo[i].dobj.catId.oid = atooid(PQgetvalue(res, i, i_oid)); - AssignDumpId(&loinfo[i].dobj); + /* Build the metadata DumpableObject */ + loinfo = (LoInfo *) pg_malloc(offsetof(LoInfo, looids) + n * sizeof(Oid)); + + loinfo->dobj.objType = DO_LARGE_OBJECT; + loinfo->dobj.catId.tableoid = LargeObjectRelationId; + loinfo->dobj.catId.oid = thisoid; + AssignDumpId(&loinfo->dobj); + + if (n > 1) + snprintf(namebuf, sizeof(namebuf), "%u..%u", thisoid, + atooid(PQgetvalue(res, i + n - 1, i_oid))); + else + snprintf(namebuf, sizeof(namebuf), "%u", thisoid); + loinfo->dobj.name = pg_strdup(namebuf); + loinfo->dacl.acl = pg_strdup(thisacl); + loinfo->dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault)); + loinfo->dacl.privtype = 0; + loinfo->dacl.initprivs = NULL; + loinfo->rolname = getRoleName(thisowner); + loinfo->numlos = n; + loinfo->looids[0] = thisoid; + /* Collect OIDs of the remaining blobs in this group */ + for (int k = 1; k < n; k++) + { + CatalogId extraID; + + loinfo->looids[k] = atooid(PQgetvalue(res, i + k, i_oid)); - loinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_oid)); - loinfo[i].dacl.acl = pg_strdup(PQgetvalue(res, i, i_lomacl)); - loinfo[i].dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault)); - loinfo[i].dacl.privtype = 0; - loinfo[i].dacl.initprivs = NULL; - loinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_lomowner)); + /* Make sure we can look up loinfo by any of the blobs' OIDs */ + extraID.tableoid = LargeObjectRelationId; + extraID.oid = loinfo->looids[k]; + recordAdditionalCatalogID(extraID, &loinfo->dobj); + } /* LOs have data */ - loinfo[i].dobj.components |= DUMP_COMPONENT_DATA; + loinfo->dobj.components |= DUMP_COMPONENT_DATA; - /* Mark whether LO has an ACL */ + /* Mark whether LO group has a non-empty ACL */ if (!PQgetisnull(res, i, i_lomacl)) - loinfo[i].dobj.components |= DUMP_COMPONENT_ACL; + loinfo->dobj.components |= DUMP_COMPONENT_ACL; /* * In binary-upgrade mode for LOs, we do *not* dump out the LO data, @@ -3653,21 +3705,22 @@ getLOs(Archive *fout) * pg_largeobject_metadata, after the dump is restored. */ if (dopt->binary_upgrade) - loinfo[i].dobj.dump &= ~DUMP_COMPONENT_DATA; - } + loinfo->dobj.dump &= ~DUMP_COMPONENT_DATA; - /* - * If we have any large objects, a "BLOBS" archive entry is needed. This - * is just a placeholder for sorting; it carries no data now. - */ - if (ntups > 0) - { + /* + * Create a "BLOBS" data item for the group, too. This is just a + * placeholder for sorting; it carries no data now. + */ lodata = (DumpableObject *) pg_malloc(sizeof(DumpableObject)); lodata->objType = DO_LARGE_OBJECT_DATA; lodata->catId = nilCatalogId; AssignDumpId(lodata); - lodata->name = pg_strdup("BLOBS"); + lodata->name = pg_strdup(namebuf); lodata->components |= DUMP_COMPONENT_DATA; + /* Set up explicit dependency from data to metadata */ + lodata->dependencies = (DumpId *) pg_malloc(sizeof(DumpId)); + lodata->dependencies[0] = loinfo->dobj.dumpId; + lodata->nDeps = lodata->allocDeps = 1; } PQclear(res); @@ -3677,123 +3730,109 @@ getLOs(Archive *fout) /* * dumpLO * - * dump the definition (metadata) of the given large object + * dump the definition (metadata) of the given large object group */ static void dumpLO(Archive *fout, const LoInfo *loinfo) { PQExpBuffer cquery = createPQExpBuffer(); - PQExpBuffer dquery = createPQExpBuffer(); - appendPQExpBuffer(cquery, - "SELECT pg_catalog.lo_create('%s');\n", - loinfo->dobj.name); - - appendPQExpBuffer(dquery, - "SELECT pg_catalog.lo_unlink('%s');\n", - loinfo->dobj.name); + /* + * The "definition" is just a newline-separated list of OIDs. We need to + * put something into the dropStmt too, but it can just be a comment. + */ + for (int i = 0; i < loinfo->numlos; i++) + appendPQExpBuffer(cquery, "%u\n", loinfo->looids[i]); if (loinfo->dobj.dump & DUMP_COMPONENT_DEFINITION) ArchiveEntry(fout, loinfo->dobj.catId, loinfo->dobj.dumpId, ARCHIVE_OPTS(.tag = loinfo->dobj.name, .owner = loinfo->rolname, - .description = "BLOB", + .description = "BLOB METADATA", .section = SECTION_PRE_DATA, .createStmt = cquery->data, - .dropStmt = dquery->data)); - - /* Dump comment if any */ - if (loinfo->dobj.dump & DUMP_COMPONENT_COMMENT) - dumpComment(fout, "LARGE OBJECT", loinfo->dobj.name, - NULL, loinfo->rolname, - loinfo->dobj.catId, 0, loinfo->dobj.dumpId); - - /* Dump security label if any */ - if (loinfo->dobj.dump & DUMP_COMPONENT_SECLABEL) - dumpSecLabel(fout, "LARGE OBJECT", loinfo->dobj.name, - NULL, loinfo->rolname, - loinfo->dobj.catId, 0, loinfo->dobj.dumpId); - - /* Dump ACL if any */ - if (loinfo->dobj.dump & DUMP_COMPONENT_ACL) - dumpACL(fout, loinfo->dobj.dumpId, InvalidDumpId, "LARGE OBJECT", - loinfo->dobj.name, NULL, - NULL, loinfo->rolname, &loinfo->dacl); + .dropStmt = "-- dummy")); + + /* + * Dump per-blob comments, seclabels, and ACLs if any. We assume these + * are rare enough that it's okay to generate retail TOC entries for them. + */ + if (loinfo->dobj.dump & (DUMP_COMPONENT_COMMENT | + DUMP_COMPONENT_SECLABEL | + DUMP_COMPONENT_ACL)) + { + for (int i = 0; i < loinfo->numlos; i++) + { + CatalogId catId; + char namebuf[32]; + + /* Build identifying info for this blob */ + catId.tableoid = loinfo->dobj.catId.tableoid; + catId.oid = loinfo->looids[i]; + snprintf(namebuf, sizeof(namebuf), "%u", loinfo->looids[i]); + + if (loinfo->dobj.dump & DUMP_COMPONENT_COMMENT) + dumpComment(fout, "LARGE OBJECT", namebuf, + NULL, loinfo->rolname, + catId, 0, loinfo->dobj.dumpId); + + if (loinfo->dobj.dump & DUMP_COMPONENT_SECLABEL) + dumpSecLabel(fout, "LARGE OBJECT", namebuf, + NULL, loinfo->rolname, + catId, 0, loinfo->dobj.dumpId); + + if (loinfo->dobj.dump & DUMP_COMPONENT_ACL) + dumpACL(fout, loinfo->dobj.dumpId, InvalidDumpId, + "LARGE OBJECT", namebuf, NULL, + NULL, loinfo->rolname, &loinfo->dacl); + } + } destroyPQExpBuffer(cquery); - destroyPQExpBuffer(dquery); } /* * dumpLOs: - * dump the data contents of all large objects + * dump the data contents of the large objects in the given group */ static int dumpLOs(Archive *fout, const void *arg) { - const char *loQry; - const char *loFetchQry; + const LoInfo *loinfo = (const LoInfo *) arg; PGconn *conn = GetConnection(fout); - PGresult *res; char buf[LOBBUFSIZE]; - int ntups; - int i; - int cnt; - pg_log_info("saving large objects"); - - /* - * Currently, we re-fetch all LO OIDs using a cursor. Consider scanning - * the already-in-memory dumpable objects instead... - */ - loQry = - "DECLARE looid CURSOR FOR " - "SELECT oid FROM pg_largeobject_metadata ORDER BY 1"; + pg_log_info("saving large objects \"%s\"", loinfo->dobj.name); - ExecuteSqlStatement(fout, loQry); + for (int i = 0; i < loinfo->numlos; i++) + { + Oid loOid = loinfo->looids[i]; + int loFd; + int cnt; - /* Command to fetch from cursor */ - loFetchQry = "FETCH 1000 IN looid"; + /* Open the LO */ + loFd = lo_open(conn, loOid, INV_READ); + if (loFd == -1) + pg_fatal("could not open large object %u: %s", + loOid, PQerrorMessage(conn)); - do - { - /* Do a fetch */ - res = ExecuteSqlQuery(fout, loFetchQry, PGRES_TUPLES_OK); + StartLO(fout, loOid); - /* Process the tuples, if any */ - ntups = PQntuples(res); - for (i = 0; i < ntups; i++) + /* Now read it in chunks, sending data to archive */ + do { - Oid loOid; - int loFd; - - loOid = atooid(PQgetvalue(res, i, 0)); - /* Open the LO */ - loFd = lo_open(conn, loOid, INV_READ); - if (loFd == -1) - pg_fatal("could not open large object %u: %s", + cnt = lo_read(conn, loFd, buf, LOBBUFSIZE); + if (cnt < 0) + pg_fatal("error reading large object %u: %s", loOid, PQerrorMessage(conn)); - StartLO(fout, loOid); - - /* Now read it in chunks, sending data to archive */ - do - { - cnt = lo_read(conn, loFd, buf, LOBBUFSIZE); - if (cnt < 0) - pg_fatal("error reading large object %u: %s", - loOid, PQerrorMessage(conn)); + WriteData(fout, buf, cnt); + } while (cnt > 0); - WriteData(fout, buf, cnt); - } while (cnt > 0); + lo_close(conn, loFd); - lo_close(conn, loFd); - - EndLO(fout, loOid); - } - - PQclear(res); - } while (ntups > 0); + EndLO(fout, loOid); + } return 1; } @@ -10623,28 +10662,34 @@ dumpDumpableObject(Archive *fout, DumpableObject *dobj) case DO_LARGE_OBJECT_DATA: if (dobj->dump & DUMP_COMPONENT_DATA) { + LoInfo *loinfo; TocEntry *te; + loinfo = (LoInfo *) findObjectByDumpId(dobj->dependencies[0]); + if (loinfo == NULL) + pg_fatal("missing metadata for large objects \"%s\"", + dobj->name); + te = ArchiveEntry(fout, dobj->catId, dobj->dumpId, ARCHIVE_OPTS(.tag = dobj->name, + .owner = loinfo->rolname, .description = "BLOBS", .section = SECTION_DATA, - .dumpFn = dumpLOs)); + .deps = dobj->dependencies, + .nDeps = dobj->nDeps, + .dumpFn = dumpLOs, + .dumpArg = loinfo)); /* * Set the TocEntry's dataLength in case we are doing a * parallel dump and want to order dump jobs by table size. * (We need some size estimate for every TocEntry with a * DataDumper function.) We don't currently have any cheap - * way to estimate the size of LOs, but it doesn't matter; - * let's just set the size to a large value so parallel dumps - * will launch this job first. If there's lots of LOs, we - * win, and if there aren't, we don't lose much. (If you want - * to improve on this, really what you should be thinking - * about is allowing LO dumping to be parallelized, not just - * getting a smarter estimate for the single TOC entry.) + * way to estimate the size of LOs, but fortunately it doesn't + * matter too much as long as we get large batches of LOs + * processed reasonably early. Assume 8K per blob. */ - te->dataLength = INT_MAX; + te->dataLength = loinfo->numlos * (pgoff_t) 8192; } break; case DO_POLICY: diff --git a/src/bin/pg_dump/pg_dump.h b/src/bin/pg_dump/pg_dump.h index 9bc93520b4..2a7c5873a0 100644 --- a/src/bin/pg_dump/pg_dump.h +++ b/src/bin/pg_dump/pg_dump.h @@ -582,11 +582,21 @@ typedef struct _defaultACLInfo char defaclobjtype; } DefaultACLInfo; +/* + * LoInfo represents a group of large objects (blobs) that share the same + * owner and ACL setting. dobj.components has the DUMP_COMPONENT_COMMENT bit + * set if any blob in the group has a comment; similarly for sec labels. + * If there are many blobs with the same owner/ACL, we can divide them into + * multiple LoInfo groups, which will each spawn a BLOB METADATA and a BLOBS + * (data) TOC entry. This allows more parallelism during restore. + */ typedef struct _loInfo { DumpableObject dobj; DumpableAcl dacl; const char *rolname; + int numlos; + Oid looids[FLEXIBLE_ARRAY_MEMBER]; } LoInfo; /* @@ -695,6 +705,7 @@ typedef struct _SubRelInfo extern TableInfo *getSchemaData(Archive *fout, int *numTablesPtr); extern void AssignDumpId(DumpableObject *dobj); +extern void recordAdditionalCatalogID(CatalogId catId, DumpableObject *dobj); extern DumpId createDumpId(void); extern DumpId getMaxDumpId(void); extern DumpableObject *findObjectByDumpId(DumpId dumpId); diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl index c8b489d94e..1da2fc6575 100644 --- a/src/bin/pg_dump/t/002_pg_dump.pl +++ b/src/bin/pg_dump/t/002_pg_dump.pl @@ -109,11 +109,11 @@ my %pgdump_runs = ( '--format=directory', '--compress=gzip:1', "--file=$tempdir/compression_gzip_dir", 'postgres', ], - # Give coverage for manually compressed blob.toc files during + # Give coverage for manually compressed blobs.toc files during # restore. compress_cmd => { program => $ENV{'GZIP_PROGRAM'}, - args => [ '-f', "$tempdir/compression_gzip_dir/blobs.toc", ], + args => [ '-f', "$tempdir/compression_gzip_dir/blobs_*.toc", ], }, # Verify that only data files were compressed glob_patterns => [ @@ -172,16 +172,6 @@ my %pgdump_runs = ( '--format=directory', '--compress=lz4:1', "--file=$tempdir/compression_lz4_dir", 'postgres', ], - # Give coverage for manually compressed blob.toc files during - # restore. - compress_cmd => { - program => $ENV{'LZ4'}, - args => [ - '-z', '-f', '--rm', - "$tempdir/compression_lz4_dir/blobs.toc", - "$tempdir/compression_lz4_dir/blobs.toc.lz4", - ], - }, # Verify that data files were compressed glob_patterns => [ "$tempdir/compression_lz4_dir/toc.dat", @@ -242,14 +232,13 @@ my %pgdump_runs = ( '--format=directory', '--compress=zstd:1', "--file=$tempdir/compression_zstd_dir", 'postgres', ], - # Give coverage for manually compressed blob.toc files during + # Give coverage for manually compressed blobs.toc files during # restore. compress_cmd => { program => $ENV{'ZSTD'}, args => [ '-z', '-f', - '--rm', "$tempdir/compression_zstd_dir/blobs.toc", - "-o", "$tempdir/compression_zstd_dir/blobs.toc.zst", + '--rm', "$tempdir/compression_zstd_dir/blobs_*.toc", ], }, # Verify that data files were compressed @@ -413,7 +402,7 @@ my %pgdump_runs = ( }, glob_patterns => [ "$tempdir/defaults_dir_format/toc.dat", - "$tempdir/defaults_dir_format/blobs.toc", + "$tempdir/defaults_dir_format/blobs_*.toc", $supports_gzip ? "$tempdir/defaults_dir_format/*.dat.gz" : "$tempdir/defaults_dir_format/*.dat", ], @@ -4858,8 +4847,13 @@ foreach my $run (sort keys %pgdump_runs) # not defined. next if (!defined($compress_program) || $compress_program eq ''); - my @full_compress_cmd = - ($compress_cmd->{program}, @{ $compress_cmd->{args} }); + # Arguments may require globbing. + my @full_compress_cmd = ($compress_program); + foreach my $arg (@{ $compress_cmd->{args} }) + { + push @full_compress_cmd, glob($arg); + } + command_ok(\@full_compress_cmd, "$run: compression commands"); } -- 2.39.3