On Wed, Mar 05, 2025 at 03:40:52PM -0500, Greg Sabino Mullane wrote: > I've seen various failures, but they always get caught quite early. > Certainly early enough to easily abort, fix perms/mounts/etc., then retry. > I think your instinct is correct that this reversion is more trouble than > its worth. I don't think the pg_upgrade docs mention taking a backup, but > that's always step 0 in my playbook, and that's the rollback plan in the > unlikely event of failure.
Thank you, Greg and Robert, for sharing your thoughts. With that, here's what I'm considering to be a reasonably complete patch set for this feature. This leaves about a month for rigorous testing and editing, so I'm hopeful it'll be ready v18. -- nathan
>From 6716e7b16a795911f55432dfd6d3c246aa8fd9fe Mon Sep 17 00:00:00 2001 From: Nathan Bossart <nat...@postgresql.org> Date: Wed, 19 Feb 2025 09:14:51 -0600 Subject: [PATCH v4 1/3] initdb: Add --no-sync-data-files. This new option instructs initdb to skip synchronizing any files in database directories and the database directories themselves, i.e., everything in the base/ subdirectory and any other tablespace directories. Other files, such as those in pg_wal/ and pg_xact/, will still be synchronized unless --no-sync is also specified. --no-sync-data-files is primarily intended for internal use by tools that separately ensure the skipped files are synchronized to disk. A follow-up commit will use this to help optimize pg_upgrade's file transfer step. Discussion: https://postgr.es/m/Zyvop-LxLXBLrZil%40nathan --- doc/src/sgml/ref/initdb.sgml | 20 +++++ src/bin/initdb/initdb.c | 10 ++- src/bin/initdb/t/001_initdb.pl | 1 + src/bin/pg_basebackup/pg_basebackup.c | 2 +- src/bin/pg_checksums/pg_checksums.c | 2 +- src/bin/pg_combinebackup/pg_combinebackup.c | 2 +- src/bin/pg_rewind/file_ops.c | 2 +- src/common/file_utils.c | 85 +++++++++++++-------- src/include/common/file_utils.h | 2 +- 9 files changed, 89 insertions(+), 37 deletions(-) diff --git a/doc/src/sgml/ref/initdb.sgml b/doc/src/sgml/ref/initdb.sgml index 0026318485a..14c401b9a99 100644 --- a/doc/src/sgml/ref/initdb.sgml +++ b/doc/src/sgml/ref/initdb.sgml @@ -527,6 +527,26 @@ PostgreSQL documentation </listitem> </varlistentry> + <varlistentry id="app-initdb-option-no-sync-data-files"> + <term><option>--no-sync-data-files</option></term> + <listitem> + <para> + By default, <command>initdb</command> safely writes all database files + to disk. This option instructs <command>initdb</command> to skip + synchronizing all files in the individual database directories and the + database directories themselves, i.e., everything in the + <filename>base</filename> subdirectory and any other tablespace + directories. Other files, such as those in <literal>pg_wal</literal> + and <literal>pg_xact</literal>, will still be synchronized unless the + <option>--no-sync</option> option is also specified. + </para> + <para> + This option is primarily intended for internal use by tools that + separately ensure the skipped files are synchronized to disk. + </para> + </listitem> + </varlistentry> + <varlistentry id="app-initdb-option-no-instructions"> <term><option>--no-instructions</option></term> <listitem> diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c index 21a0fe3ecd9..22b7d31b165 100644 --- a/src/bin/initdb/initdb.c +++ b/src/bin/initdb/initdb.c @@ -168,6 +168,7 @@ static bool data_checksums = true; static char *xlog_dir = NULL; static int wal_segment_size_mb = (DEFAULT_XLOG_SEG_SIZE) / (1024 * 1024); static DataDirSyncMethod sync_method = DATA_DIR_SYNC_METHOD_FSYNC; +static bool sync_data_files = true; /* internal vars */ @@ -2566,6 +2567,7 @@ usage(const char *progname) printf(_(" -L DIRECTORY where to find the input files\n")); printf(_(" -n, --no-clean do not clean up after errors\n")); printf(_(" -N, --no-sync do not wait for changes to be written safely to disk\n")); + printf(_(" --no-sync-data-files do not sync files within database directories\n")); printf(_(" --no-instructions do not print instructions for next steps\n")); printf(_(" -s, --show show internal settings, then exit\n")); printf(_(" --sync-method=METHOD set method for syncing files to disk\n")); @@ -3208,6 +3210,7 @@ main(int argc, char *argv[]) {"icu-rules", required_argument, NULL, 18}, {"sync-method", required_argument, NULL, 19}, {"no-data-checksums", no_argument, NULL, 20}, + {"no-sync-data-files", no_argument, NULL, 21}, {NULL, 0, NULL, 0} }; @@ -3402,6 +3405,9 @@ main(int argc, char *argv[]) case 20: data_checksums = false; break; + case 21: + sync_data_files = false; + break; default: /* getopt_long already emitted a complaint */ pg_log_error_hint("Try \"%s --help\" for more information.", progname); @@ -3453,7 +3459,7 @@ main(int argc, char *argv[]) fputs(_("syncing data to disk ... "), stdout); fflush(stdout); - sync_pgdata(pg_data, PG_VERSION_NUM, sync_method); + sync_pgdata(pg_data, PG_VERSION_NUM, sync_method, sync_data_files); check_ok(); return 0; } @@ -3516,7 +3522,7 @@ main(int argc, char *argv[]) { fputs(_("syncing data to disk ... "), stdout); fflush(stdout); - sync_pgdata(pg_data, PG_VERSION_NUM, sync_method); + sync_pgdata(pg_data, PG_VERSION_NUM, sync_method, sync_data_files); check_ok(); } else diff --git a/src/bin/initdb/t/001_initdb.pl b/src/bin/initdb/t/001_initdb.pl index 01cc4a1602b..15dd10ce40a 100644 --- a/src/bin/initdb/t/001_initdb.pl +++ b/src/bin/initdb/t/001_initdb.pl @@ -76,6 +76,7 @@ command_like( 'checksums are enabled in control file'); command_ok([ 'initdb', '--sync-only', $datadir ], 'sync only'); +command_ok([ 'initdb', '--sync-only', '--no-sync-data-files', $datadir ], '--no-sync-data-files'); command_fails([ 'initdb', $datadir ], 'existing data directory'); if ($supports_syncfs) diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c index dc0c805137a..bc94c114d27 100644 --- a/src/bin/pg_basebackup/pg_basebackup.c +++ b/src/bin/pg_basebackup/pg_basebackup.c @@ -2310,7 +2310,7 @@ BaseBackup(char *compression_algorithm, char *compression_detail, } else { - (void) sync_pgdata(basedir, serverVersion, sync_method); + (void) sync_pgdata(basedir, serverVersion, sync_method, true); } } diff --git a/src/bin/pg_checksums/pg_checksums.c b/src/bin/pg_checksums/pg_checksums.c index 867aeddc601..f20be82862a 100644 --- a/src/bin/pg_checksums/pg_checksums.c +++ b/src/bin/pg_checksums/pg_checksums.c @@ -633,7 +633,7 @@ main(int argc, char *argv[]) if (do_sync) { pg_log_info("syncing data directory"); - sync_pgdata(DataDir, PG_VERSION_NUM, sync_method); + sync_pgdata(DataDir, PG_VERSION_NUM, sync_method, true); } pg_log_info("updating control file"); diff --git a/src/bin/pg_combinebackup/pg_combinebackup.c b/src/bin/pg_combinebackup/pg_combinebackup.c index 5864ec574fb..c0ec09485c3 100644 --- a/src/bin/pg_combinebackup/pg_combinebackup.c +++ b/src/bin/pg_combinebackup/pg_combinebackup.c @@ -420,7 +420,7 @@ main(int argc, char *argv[]) else { pg_log_debug("recursively fsyncing \"%s\"", opt.output); - sync_pgdata(opt.output, version * 10000, opt.sync_method); + sync_pgdata(opt.output, version * 10000, opt.sync_method, true); } } diff --git a/src/bin/pg_rewind/file_ops.c b/src/bin/pg_rewind/file_ops.c index 467845419ed..55659ce201f 100644 --- a/src/bin/pg_rewind/file_ops.c +++ b/src/bin/pg_rewind/file_ops.c @@ -296,7 +296,7 @@ sync_target_dir(void) if (!do_sync || dry_run) return; - sync_pgdata(datadir_target, PG_VERSION_NUM, sync_method); + sync_pgdata(datadir_target, PG_VERSION_NUM, sync_method, true); } diff --git a/src/common/file_utils.c b/src/common/file_utils.c index 0e3cfede935..78e272916f5 100644 --- a/src/common/file_utils.c +++ b/src/common/file_utils.c @@ -50,7 +50,8 @@ static int pre_sync_fname(const char *fname, bool isdir); #endif static void walkdir(const char *path, int (*action) (const char *fname, bool isdir), - bool process_symlinks); + bool process_symlinks, + const char *exclude_dir); #ifdef HAVE_SYNCFS @@ -93,11 +94,15 @@ do_syncfs(const char *path) * syncing, and might not have privileges to write at all. * * serverVersion indicates the version of the server to be sync'd. + * + * If sync_data_files is false, this function skips syncing "base/" and any + * other tablespace directories. */ void sync_pgdata(const char *pg_data, int serverVersion, - DataDirSyncMethod sync_method) + DataDirSyncMethod sync_method, + bool sync_data_files) { bool xlog_is_symlink; char pg_wal[MAXPGPATH]; @@ -147,30 +152,33 @@ sync_pgdata(const char *pg_data, do_syncfs(pg_data); /* If any tablespaces are configured, sync each of those. */ - dir = opendir(pg_tblspc); - if (dir == NULL) - pg_log_error("could not open directory \"%s\": %m", - pg_tblspc); - else + if (sync_data_files) { - while (errno = 0, (de = readdir(dir)) != NULL) + dir = opendir(pg_tblspc); + if (dir == NULL) + pg_log_error("could not open directory \"%s\": %m", + pg_tblspc); + else { - char subpath[MAXPGPATH * 2]; + while (errno = 0, (de = readdir(dir)) != NULL) + { + char subpath[MAXPGPATH * 2]; - if (strcmp(de->d_name, ".") == 0 || - strcmp(de->d_name, "..") == 0) - continue; + if (strcmp(de->d_name, ".") == 0 || + strcmp(de->d_name, "..") == 0) + continue; - snprintf(subpath, sizeof(subpath), "%s/%s", - pg_tblspc, de->d_name); - do_syncfs(subpath); - } + snprintf(subpath, sizeof(subpath), "%s/%s", + pg_tblspc, de->d_name); + do_syncfs(subpath); + } - if (errno) - pg_log_error("could not read directory \"%s\": %m", - pg_tblspc); + if (errno) + pg_log_error("could not read directory \"%s\": %m", + pg_tblspc); - (void) closedir(dir); + (void) closedir(dir); + } } /* If pg_wal is a symlink, process that too. */ @@ -182,15 +190,21 @@ sync_pgdata(const char *pg_data, case DATA_DIR_SYNC_METHOD_FSYNC: { + char *exclude_dir = NULL; + + if (!sync_data_files) + exclude_dir = psprintf("%s/base", pg_data); + /* * If possible, hint to the kernel that we're soon going to * fsync the data directory and its contents. */ #ifdef PG_FLUSH_DATA_WORKS - walkdir(pg_data, pre_sync_fname, false); + walkdir(pg_data, pre_sync_fname, false, exclude_dir); if (xlog_is_symlink) - walkdir(pg_wal, pre_sync_fname, false); - walkdir(pg_tblspc, pre_sync_fname, true); + walkdir(pg_wal, pre_sync_fname, false, NULL); + if (sync_data_files) + walkdir(pg_tblspc, pre_sync_fname, true, NULL); #endif /* @@ -203,10 +217,14 @@ sync_pgdata(const char *pg_data, * get fsync'd twice. That's not an expected case so we don't * worry about optimizing it. */ - walkdir(pg_data, fsync_fname, false); + walkdir(pg_data, fsync_fname, false, exclude_dir); if (xlog_is_symlink) - walkdir(pg_wal, fsync_fname, false); - walkdir(pg_tblspc, fsync_fname, true); + walkdir(pg_wal, fsync_fname, false, NULL); + if (sync_data_files) + walkdir(pg_tblspc, fsync_fname, true, NULL); + + if (exclude_dir) + pfree(exclude_dir); } break; } @@ -245,10 +263,10 @@ sync_dir_recurse(const char *dir, DataDirSyncMethod sync_method) * fsync the data directory and its contents. */ #ifdef PG_FLUSH_DATA_WORKS - walkdir(dir, pre_sync_fname, false); + walkdir(dir, pre_sync_fname, false, NULL); #endif - walkdir(dir, fsync_fname, false); + walkdir(dir, fsync_fname, false, NULL); } break; } @@ -264,6 +282,9 @@ sync_dir_recurse(const char *dir, DataDirSyncMethod sync_method) * ignored in subdirectories, ie we intentionally don't pass down the * process_symlinks flag to recursive calls. * + * If exclude_dir is not NULL, it specifies a directory path to skip + * processing. + * * Errors are reported but not considered fatal. * * See also walkdir in fd.c, which is a backend version of this logic. @@ -271,11 +292,15 @@ sync_dir_recurse(const char *dir, DataDirSyncMethod sync_method) static void walkdir(const char *path, int (*action) (const char *fname, bool isdir), - bool process_symlinks) + bool process_symlinks, + const char *exclude_dir) { DIR *dir; struct dirent *de; + if (exclude_dir && strcmp(exclude_dir, path) == 0) + return; + dir = opendir(path); if (dir == NULL) { @@ -299,7 +324,7 @@ walkdir(const char *path, (*action) (subpath, false); break; case PGFILETYPE_DIR: - walkdir(subpath, action, false); + walkdir(subpath, action, false, exclude_dir); break; default: diff --git a/src/include/common/file_utils.h b/src/include/common/file_utils.h index a832210adc1..8274bc877ab 100644 --- a/src/include/common/file_utils.h +++ b/src/include/common/file_utils.h @@ -35,7 +35,7 @@ struct iovec; /* avoid including port/pg_iovec.h here */ #ifdef FRONTEND extern int fsync_fname(const char *fname, bool isdir); extern void sync_pgdata(const char *pg_data, int serverVersion, - DataDirSyncMethod sync_method); + DataDirSyncMethod sync_method, bool sync_data_files); extern void sync_dir_recurse(const char *dir, DataDirSyncMethod sync_method); extern int durable_rename(const char *oldfile, const char *newfile); extern int fsync_parent_path(const char *fname); -- 2.39.5 (Apple Git-154)
>From e6dc183b8a80a32f6ca52b0d21a173d1b291deea Mon Sep 17 00:00:00 2001 From: Nathan Bossart <nat...@postgresql.org> Date: Wed, 19 Feb 2025 11:25:28 -0600 Subject: [PATCH v4 2/3] pg_dump: Add --sequence-data. This new option instructs pg_dump to dump sequence data when the --no-data, --schema-only, or --statistics-only option is specified. This was originally considered for commit a7e5457db8, but it was left out at that time because there was no known use-case. A follow-up commit will use this to optimize pg_upgrade's file transfer step. Discussion: https://postgr.es/m/Zyvop-LxLXBLrZil%40nathan --- doc/src/sgml/ref/pg_dump.sgml | 11 +++++++++++ src/bin/pg_dump/pg_dump.c | 10 ++-------- src/bin/pg_dump/t/002_pg_dump.pl | 1 + src/bin/pg_upgrade/dump.c | 2 +- src/test/modules/test_pg_dump/t/001_base.pl | 2 +- 5 files changed, 16 insertions(+), 10 deletions(-) diff --git a/doc/src/sgml/ref/pg_dump.sgml b/doc/src/sgml/ref/pg_dump.sgml index 1975054d7bf..b05f16995c3 100644 --- a/doc/src/sgml/ref/pg_dump.sgml +++ b/doc/src/sgml/ref/pg_dump.sgml @@ -1289,6 +1289,17 @@ PostgreSQL documentation </listitem> </varlistentry> + <varlistentry> + <term><option>--sequence-data</option></term> + <listitem> + <para> + Include sequence data in the dump. This is the default behavior except + when <option>--no-data</option>, <option>--schema-only</option>, or + <option>--statistics-only</option> is specified. + </para> + </listitem> + </varlistentry> + <varlistentry> <term><option>--serializable-deferrable</option></term> <listitem> diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c index 4f4ad2ee150..f63215eb3f9 100644 --- a/src/bin/pg_dump/pg_dump.c +++ b/src/bin/pg_dump/pg_dump.c @@ -517,6 +517,7 @@ main(int argc, char **argv) {"sync-method", required_argument, NULL, 15}, {"filter", required_argument, NULL, 16}, {"exclude-extension", required_argument, NULL, 17}, + {"sequence-data", no_argument, &dopt.sequence_data, 1}, {NULL, 0, NULL, 0} }; @@ -803,14 +804,6 @@ main(int argc, char **argv) if (dopt.column_inserts && dopt.dump_inserts == 0) dopt.dump_inserts = DUMP_DEFAULT_ROWS_PER_INSERT; - /* - * Binary upgrade mode implies dumping sequence data even in schema-only - * mode. This is not exposed as a separate option, but kept separate - * internally for clarity. - */ - if (dopt.binary_upgrade) - dopt.sequence_data = 1; - if (data_only && schema_only) pg_fatal("options -s/--schema-only and -a/--data-only cannot be used together"); if (schema_only && statistics_only) @@ -1275,6 +1268,7 @@ help(const char *progname) printf(_(" --quote-all-identifiers quote all identifiers, even if not key words\n")); printf(_(" --rows-per-insert=NROWS number of rows per INSERT; implies --inserts\n")); printf(_(" --section=SECTION dump named section (pre-data, data, or post-data)\n")); + printf(_(" --sequence-data include sequence data in dump\n")); printf(_(" --serializable-deferrable wait until the dump can run without anomalies\n")); printf(_(" --snapshot=SNAPSHOT use given snapshot for the dump\n")); printf(_(" --statistics-only dump only the statistics, not schema or data\n")); diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl index c7bffc1b045..8ae6c5374fc 100644 --- a/src/bin/pg_dump/t/002_pg_dump.pl +++ b/src/bin/pg_dump/t/002_pg_dump.pl @@ -66,6 +66,7 @@ my %pgdump_runs = ( '--file' => "$tempdir/binary_upgrade.dump", '--no-password', '--no-data', + '--sequence-data', '--binary-upgrade', '--dbname' => 'postgres', # alternative way to specify database ], diff --git a/src/bin/pg_upgrade/dump.c b/src/bin/pg_upgrade/dump.c index 23fe7280a16..b8fd0d0acee 100644 --- a/src/bin/pg_upgrade/dump.c +++ b/src/bin/pg_upgrade/dump.c @@ -52,7 +52,7 @@ generate_old_dump(void) snprintf(log_file_name, sizeof(log_file_name), DB_DUMP_LOG_FILE_MASK, old_db->db_oid); parallel_exec_prog(log_file_name, NULL, - "\"%s/pg_dump\" %s --no-data %s --quote-all-identifiers " + "\"%s/pg_dump\" %s --no-data %s --sequence-data --quote-all-identifiers " "--binary-upgrade --format=custom %s --no-sync --file=\"%s/%s\" %s", new_cluster.bindir, cluster_conn_opts(&old_cluster), log_opts.verbose ? "--verbose" : "", diff --git a/src/test/modules/test_pg_dump/t/001_base.pl b/src/test/modules/test_pg_dump/t/001_base.pl index 9b2a90b0469..27c6c2ab0f3 100644 --- a/src/test/modules/test_pg_dump/t/001_base.pl +++ b/src/test/modules/test_pg_dump/t/001_base.pl @@ -48,7 +48,7 @@ my %pgdump_runs = ( dump_cmd => [ 'pg_dump', '--no-sync', "--file=$tempdir/binary_upgrade.sql", '--schema-only', - '--binary-upgrade', '--dbname=postgres', + '--sequence-data', '--binary-upgrade', '--dbname=postgres', ], }, clean => { -- 2.39.5 (Apple Git-154)
>From ecd5b53daefd3187195e5a8fbf47e0a8a278bf30 Mon Sep 17 00:00:00 2001 From: Nathan Bossart <nat...@postgresql.org> Date: Wed, 5 Mar 2025 17:36:54 -0600 Subject: [PATCH v4 3/3] pg_upgrade: Add --swap for faster file transfer. This new option instructs pg_upgrade to move the data directories from the old cluster to the new cluster and then to replace the catalog files with those generated for the new cluster. This mode can outperform --link, --clone, --copy, and --copy-file-range, especially on clusters with many relations. However, this mode creates many garbage files in the old cluster, which can prolong the file synchronization step. To handle that, we use "initdb --sync-only --no-sync-data-files" for file synchronization, and we synchronize the catalog files as they are transferred. We assume that the database files transferred from the old cluster were synchronized prior to upgrade. This mode also complicates reverting to the old cluster, so we recommend restoring from backup upon failure during or after file transfer. The new mode is limited to clusters located in the same file system and to upgrades from version 10 and newer. Discussion: https://postgr.es/m/Zyvop-LxLXBLrZil%40nathan --- doc/src/sgml/ref/pgupgrade.sgml | 59 ++++- src/bin/pg_upgrade/check.c | 29 ++- src/bin/pg_upgrade/controldata.c | 23 +- src/bin/pg_upgrade/dump.c | 4 +- src/bin/pg_upgrade/file.c | 16 +- src/bin/pg_upgrade/info.c | 4 +- src/bin/pg_upgrade/option.c | 7 + src/bin/pg_upgrade/pg_upgrade.c | 16 +- src/bin/pg_upgrade/pg_upgrade.h | 5 +- src/bin/pg_upgrade/relfilenumber.c | 358 +++++++++++++++++++++++++++++ src/common/file_utils.c | 14 +- src/include/common/file_utils.h | 1 + 12 files changed, 505 insertions(+), 31 deletions(-) diff --git a/doc/src/sgml/ref/pgupgrade.sgml b/doc/src/sgml/ref/pgupgrade.sgml index 7bdd85c5cff..08278232e71 100644 --- a/doc/src/sgml/ref/pgupgrade.sgml +++ b/doc/src/sgml/ref/pgupgrade.sgml @@ -244,7 +244,8 @@ PostgreSQL documentation <listitem> <para> Copy files to the new cluster. This is the default. (See also - <option>--link</option> and <option>--clone</option>.) + <option>--link</option>, <option>--clone</option>, + <option>--copy-file-range</option>, and <option>--swap</option>.) </para> </listitem> </varlistentry> @@ -262,6 +263,32 @@ PostgreSQL documentation </listitem> </varlistentry> + <varlistentry> + <term><option>--swap</option></term> + <listitem> + <para> + Move the data directories from the old cluster to the new cluster. + Then, replace the catalog files with those generated for the new + cluster. This mode can outperform <option>--link</option>, + <option>--clone</option>, <option>--copy</option>, and + <option>--copy-file-range</option>, especially on clusters with many + relations. + </para> + <para> + However, this mode creates many garbage files in the old cluster, which + can prolong the file synchronization step if + <option>--sync-method=syncfs</option> is used. Therefore, it is + recommended to use <option>--sync-method=fsync</option> with + <option>--swap</option>. + </para> + <para> + Additionally, once the file transfer step begins, the old cluster will + be destructively modified and therefore will no longer be safe to + start. See <xref linkend="pgupgrade-step-revert"/> for details. + </para> + </listitem> + </varlistentry> + <varlistentry> <term><option>--sync-method=</option><replaceable>method</replaceable></term> <listitem> @@ -530,6 +557,10 @@ NET STOP postgresql-&majorversion; is started. Clone mode also requires that the old and new data directories be in the same file system. This mode is only available on certain operating systems and file systems. + Swap mode may be the fastest if there are many relations, but you will not + be able to access your old cluster once the file transfer step begins. + Swap mode also requires that the old and new cluster data directories be + in the same file system. </para> <para> @@ -889,6 +920,32 @@ psql --username=postgres --file=script.sql postgres </itemizedlist></para> </listitem> + + <listitem> + <para> + If the <option>--swap</option> option was used, the old cluster might + be destructively modified: + + <itemizedlist> + <listitem> + <para> + If <command>pg_upgrade</command> aborts before reporting that the + old cluster is no longer safe to start, the old cluster was + unmodified; it can be restarted. + </para> + </listitem> + + <listitem> + <para> + If <command>pg_upgrade</command> has reported that the old cluster + is no longer safe to start, the old cluster was destructively + modified. The old cluster will need to be restored from backup in + this case. + </para> + </listitem> + </itemizedlist> + </para> + </listitem> </itemizedlist></para> </step> </procedure> diff --git a/src/bin/pg_upgrade/check.c b/src/bin/pg_upgrade/check.c index 88db8869b6e..5405ed7bc8f 100644 --- a/src/bin/pg_upgrade/check.c +++ b/src/bin/pg_upgrade/check.c @@ -709,7 +709,34 @@ check_new_cluster(void) check_copy_file_range(); break; case TRANSFER_MODE_LINK: - check_hard_link(); + check_hard_link(TRANSFER_MODE_LINK); + break; + case TRANSFER_MODE_SWAP: + + /* + * We do the hard link check for --swap, too, since it's an easy + * way to verify the clusters are in the same file system. This + * allows us to take some shortcuts in the file synchronization + * step. With some more effort, we could probably support the + * separate-file-system use case, but this mode is unlikely to + * offer much benefit if we have to copy the files across file + * system boundaries. + */ + check_hard_link(TRANSFER_MODE_SWAP); + + /* + * There are a few known issues with using --swap to upgrade from + * versions older than 10. For example, the sequence tuple format + * changed in v10, and the visibility map format changed in 9.6. + * While such problems are not insurmountable (and we may have to + * deal with similar problems in the future, anyway), it doesn't + * seem worth the effort to support swap mode for upgrades from + * long-unsupported versions. + */ + if (GET_MAJOR_VERSION(old_cluster.major_version) < 1000) + pg_fatal("Swap mode can only upgrade clusters from PostgreSQL version %s and later.", + "10"); + break; } diff --git a/src/bin/pg_upgrade/controldata.c b/src/bin/pg_upgrade/controldata.c index bd49ea867bf..391ed3e1085 100644 --- a/src/bin/pg_upgrade/controldata.c +++ b/src/bin/pg_upgrade/controldata.c @@ -751,11 +751,15 @@ check_control_data(ControlData *oldctrl, void -disable_old_cluster(void) +disable_old_cluster(transferMode transfer_mode) { char old_path[MAXPGPATH], new_path[MAXPGPATH]; + /* only used for --link and --swap */ + Assert(transfer_mode == TRANSFER_MODE_LINK || + transfer_mode == TRANSFER_MODE_SWAP); + /* rename pg_control so old server cannot be accidentally started */ prep_status("Adding \".old\" suffix to old global/pg_control"); @@ -766,10 +770,15 @@ disable_old_cluster(void) old_path, new_path); check_ok(); - pg_log(PG_REPORT, "\n" - "If you want to start the old cluster, you will need to remove\n" - "the \".old\" suffix from %s/global/pg_control.old.\n" - "Because \"link\" mode was used, the old cluster cannot be safely\n" - "started once the new cluster has been started.", - old_cluster.pgdata); + if (transfer_mode == TRANSFER_MODE_LINK) + pg_log(PG_REPORT, "\n" + "If you want to start the old cluster, you will need to remove\n" + "the \".old\" suffix from %s/global/pg_control.old.\n" + "Because \"link\" mode was used, the old cluster cannot be safely\n" + "started once the new cluster has been started.", + old_cluster.pgdata); + else + pg_log(PG_REPORT, "\n" + "Because \"swap\" mode was used, the old cluster can no longer be\n" + "safely started."); } diff --git a/src/bin/pg_upgrade/dump.c b/src/bin/pg_upgrade/dump.c index b8fd0d0acee..23cb08e8347 100644 --- a/src/bin/pg_upgrade/dump.c +++ b/src/bin/pg_upgrade/dump.c @@ -52,9 +52,11 @@ generate_old_dump(void) snprintf(log_file_name, sizeof(log_file_name), DB_DUMP_LOG_FILE_MASK, old_db->db_oid); parallel_exec_prog(log_file_name, NULL, - "\"%s/pg_dump\" %s --no-data %s --sequence-data --quote-all-identifiers " + "\"%s/pg_dump\" %s --no-data %s %s --quote-all-identifiers " "--binary-upgrade --format=custom %s --no-sync --file=\"%s/%s\" %s", new_cluster.bindir, cluster_conn_opts(&old_cluster), + (user_opts.transfer_mode == TRANSFER_MODE_SWAP) ? + "" : "--sequence-data", log_opts.verbose ? "--verbose" : "", user_opts.do_statistics ? "" : "--no-statistics", log_opts.dumpdir, diff --git a/src/bin/pg_upgrade/file.c b/src/bin/pg_upgrade/file.c index 7fd1991204a..4fe784e8b94 100644 --- a/src/bin/pg_upgrade/file.c +++ b/src/bin/pg_upgrade/file.c @@ -434,18 +434,28 @@ check_copy_file_range(void) } void -check_hard_link(void) +check_hard_link(transferMode transfer_mode) { char existing_file[MAXPGPATH]; char new_link_file[MAXPGPATH]; + /* only used for --link and --swap */ + Assert(transfer_mode == TRANSFER_MODE_LINK || + transfer_mode == TRANSFER_MODE_SWAP); + snprintf(existing_file, sizeof(existing_file), "%s/PG_VERSION", old_cluster.pgdata); snprintf(new_link_file, sizeof(new_link_file), "%s/PG_VERSION.linktest", new_cluster.pgdata); unlink(new_link_file); /* might fail */ if (link(existing_file, new_link_file) < 0) - pg_fatal("could not create hard link between old and new data directories: %m\n" - "In link mode the old and new data directories must be on the same file system."); + { + if (transfer_mode == TRANSFER_MODE_LINK) + pg_fatal("could not create hard link between old and new data directories: %m\n" + "In link mode the old and new data directories must be on the same file system."); + else + pg_fatal("could not create hard link between old and new data directories: %m\n" + "In swap mode the old and new data directories must be on the same file system."); + } unlink(new_link_file); } diff --git a/src/bin/pg_upgrade/info.c b/src/bin/pg_upgrade/info.c index ad52de8b607..4b7a56f5b3b 100644 --- a/src/bin/pg_upgrade/info.c +++ b/src/bin/pg_upgrade/info.c @@ -490,7 +490,7 @@ get_rel_infos_query(void) " FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n " " ON c.relnamespace = n.oid " " WHERE relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) ") AND " + CppAsString2(RELKIND_MATVIEW) "%s) AND " /* exclude possible orphaned temp tables */ " ((n.nspname !~ '^pg_temp_' AND " " n.nspname !~ '^pg_toast_temp_' AND " @@ -499,6 +499,8 @@ get_rel_infos_query(void) " c.oid >= %u::pg_catalog.oid) OR " " (n.nspname = 'pg_catalog' AND " " relname IN ('pg_largeobject') ))), ", + (user_opts.transfer_mode == TRANSFER_MODE_SWAP) ? + ", " CppAsString2(RELKIND_SEQUENCE) : "", FirstNormalObjectId); /* diff --git a/src/bin/pg_upgrade/option.c b/src/bin/pg_upgrade/option.c index 188dd8d8a8b..7fd7f1d33fc 100644 --- a/src/bin/pg_upgrade/option.c +++ b/src/bin/pg_upgrade/option.c @@ -62,6 +62,7 @@ parseCommandLine(int argc, char *argv[]) {"sync-method", required_argument, NULL, 4}, {"no-statistics", no_argument, NULL, 5}, {"set-char-signedness", required_argument, NULL, 6}, + {"swap", no_argument, NULL, 7}, {NULL, 0, NULL, 0} }; @@ -228,6 +229,11 @@ parseCommandLine(int argc, char *argv[]) else pg_fatal("invalid argument for option %s", "--set-char-signedness"); break; + + case 7: + user_opts.transfer_mode = TRANSFER_MODE_SWAP; + break; + default: fprintf(stderr, _("Try \"%s --help\" for more information.\n"), os_info.progname); @@ -325,6 +331,7 @@ usage(void) printf(_(" --no-statistics do not import statistics from old cluster\n")); printf(_(" --set-char-signedness=OPTION set new cluster char signedness to \"signed\" or\n" " \"unsigned\"\n")); + printf(_(" --swap move data directories to new cluster\n")); printf(_(" --sync-method=METHOD set method for syncing files to disk\n")); printf(_(" -?, --help show this help, then exit\n")); printf(_("\n" diff --git a/src/bin/pg_upgrade/pg_upgrade.c b/src/bin/pg_upgrade/pg_upgrade.c index 174cd920840..9295e46aed3 100644 --- a/src/bin/pg_upgrade/pg_upgrade.c +++ b/src/bin/pg_upgrade/pg_upgrade.c @@ -170,12 +170,14 @@ main(int argc, char **argv) /* * Most failures happen in create_new_objects(), which has completed at - * this point. We do this here because it is just before linking, which - * will link the old and new cluster data files, preventing the old - * cluster from being safely started once the new cluster is started. + * this point. We do this here because it is just before file transfer, + * which for --link will make it unsafe to start the old cluster once the + * new cluster is started, and for --swap will make it unsafe to start the + * old cluster at all. */ - if (user_opts.transfer_mode == TRANSFER_MODE_LINK) - disable_old_cluster(); + if (user_opts.transfer_mode == TRANSFER_MODE_LINK || + user_opts.transfer_mode == TRANSFER_MODE_SWAP) + disable_old_cluster(user_opts.transfer_mode); transfer_all_new_tablespaces(&old_cluster.dbarr, &new_cluster.dbarr, old_cluster.pgdata, new_cluster.pgdata); @@ -212,8 +214,10 @@ main(int argc, char **argv) { prep_status("Sync data directory to disk"); exec_prog(UTILITY_LOG_FILE, NULL, true, true, - "\"%s/initdb\" --sync-only \"%s\" --sync-method %s", + "\"%s/initdb\" --sync-only %s \"%s\" --sync-method %s", new_cluster.bindir, + (user_opts.transfer_mode == TRANSFER_MODE_SWAP) ? + "--no-sync-data-files" : "", new_cluster.pgdata, user_opts.sync_method); check_ok(); diff --git a/src/bin/pg_upgrade/pg_upgrade.h b/src/bin/pg_upgrade/pg_upgrade.h index f4e375d27c7..120c38929d4 100644 --- a/src/bin/pg_upgrade/pg_upgrade.h +++ b/src/bin/pg_upgrade/pg_upgrade.h @@ -262,6 +262,7 @@ typedef enum TRANSFER_MODE_COPY, TRANSFER_MODE_COPY_FILE_RANGE, TRANSFER_MODE_LINK, + TRANSFER_MODE_SWAP, } transferMode; /* @@ -391,7 +392,7 @@ void create_script_for_old_cluster_deletion(char **deletion_script_file_name); void get_control_data(ClusterInfo *cluster); void check_control_data(ControlData *oldctrl, ControlData *newctrl); -void disable_old_cluster(void); +void disable_old_cluster(transferMode transfer_mode); /* dump.c */ @@ -423,7 +424,7 @@ void rewriteVisibilityMap(const char *fromfile, const char *tofile, const char *schemaName, const char *relName); void check_file_clone(void); void check_copy_file_range(void); -void check_hard_link(void); +void check_hard_link(transferMode transfer_mode); /* fopen_priv() is no longer different from fopen() */ #define fopen_priv(path, mode) fopen(path, mode) diff --git a/src/bin/pg_upgrade/relfilenumber.c b/src/bin/pg_upgrade/relfilenumber.c index 8c23c583172..2abe90dd239 100644 --- a/src/bin/pg_upgrade/relfilenumber.c +++ b/src/bin/pg_upgrade/relfilenumber.c @@ -11,11 +11,92 @@ #include <sys/stat.h> +#include "common/file_perm.h" +#include "common/file_utils.h" +#include "common/int.h" +#include "common/logging.h" #include "pg_upgrade.h" static void transfer_single_new_db(FileNameMap *maps, int size, char *old_tablespace); static void transfer_relfile(FileNameMap *map, const char *type_suffix, bool vm_must_add_frozenbit); +/* + * The following set of sync_queue_* functions are used for --swap to reduce + * the amount of time spent synchronizing the swapped catalog files. When a + * file is added to the queue, we also alert the file system that we'd like it + * to be persisted to disk in the near future (if that operation is supported + * by the current platform). Once the queue is full, all of the files are + * synchronized to disk. This strategy should generally be much faster than + * simply calling fsync() on the files right away. + * + * The general usage pattern should be something like: + * + * for (int i = 0; i < num_files; i++) + * sync_queue_push(files[i]); + * + * // be sure to sync any remaining files in the queue + * sync_queue_sync_all(); + * synq_queue_destroy(); + */ + +#define SYNC_QUEUE_MAX_LEN (1024) + +static char *sync_queue[SYNC_QUEUE_MAX_LEN]; +static bool sync_queue_inited; +static int sync_queue_len; + +static inline void +sync_queue_init(void) +{ + if (sync_queue_inited) + return; + + sync_queue_inited = true; + for (int i = 0; i < SYNC_QUEUE_MAX_LEN; i++) + sync_queue[i] = palloc(MAXPGPATH); +} + +static inline void +sync_queue_sync_all(void) +{ + if (!sync_queue_inited) + return; + + for (int i = 0; i < sync_queue_len; i++) + { + if (fsync_fname(sync_queue[i], false) != 0) + pg_fatal("could not synchronize file \"%s\": %m", sync_queue[i]); + } + + sync_queue_len = 0; +} + +static inline void +sync_queue_push(const char *fname) +{ + sync_queue_init(); + + pre_sync_fname(fname, false); + + strncpy(sync_queue[sync_queue_len++], fname, MAXPGPATH); + if (sync_queue_len >= SYNC_QUEUE_MAX_LEN) + sync_queue_sync_all(); +} + +static inline void +sync_queue_destroy(void) +{ + if (!sync_queue_inited) + return; + + sync_queue_inited = false; + sync_queue_len = 0; + for (int i = 0; i < SYNC_QUEUE_MAX_LEN; i++) + { + pfree(sync_queue[i]); + sync_queue[i] = NULL; + } +} /* * transfer_all_new_tablespaces() @@ -41,6 +122,9 @@ transfer_all_new_tablespaces(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr, case TRANSFER_MODE_LINK: prep_status_progress("Linking user relation files"); break; + case TRANSFER_MODE_SWAP: + prep_status_progress("Swapping data directories"); + break; } /* @@ -125,6 +209,261 @@ transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr, /* We allocate something even for n_maps == 0 */ pg_free(mappings); } + + /* + * Make sure anything pending synchronization in swap mode is fully + * persisted to disk. This is a no-op for other transfer modes. + */ + sync_queue_sync_all(); + sync_queue_destroy(); +} + +/* + * prepare_for_swap() + * + * This function durably moves the database directories from the old cluster to + * the new cluster in preparation for moving the pg_restore-generated catalog + * files into place. Returns false if the database with the given OID does not + * have a directory in the given tablespace, otherwise returns true. + */ +static bool +prepare_for_swap(const char *old_tablespace, Oid db_oid, + char *old_cat, char *new_dat, char *moved_dat) +{ + const char *new_tablespace; + const char *old_tblspc_suffix; + const char *new_tblspc_suffix; + char old_tblspc[MAXPGPATH]; + char new_tblspc[MAXPGPATH]; + char moved_tblspc[MAXPGPATH]; + char old_dat[MAXPGPATH]; + struct stat st; + + if (strcmp(old_tablespace, old_cluster.pgdata) == 0) + { + new_tablespace = new_cluster.pgdata; + new_tblspc_suffix = "/base"; + old_tblspc_suffix = "/base"; + } + else + { + new_tablespace = old_tablespace; + new_tblspc_suffix = new_cluster.tablespace_suffix; + old_tblspc_suffix = old_cluster.tablespace_suffix; + } + + snprintf(old_tblspc, sizeof(old_tblspc), "%s%s", old_tablespace, old_tblspc_suffix); + snprintf(moved_tblspc, sizeof(moved_tblspc), "%s_moved", old_tblspc); + snprintf(old_cat, MAXPGPATH, "%s/%u_old_cat", moved_tblspc, db_oid); + snprintf(new_tblspc, sizeof(new_tblspc), "%s%s", new_tablespace, new_tblspc_suffix); + snprintf(new_dat, MAXPGPATH, "%s/%u", new_tblspc, db_oid); + snprintf(moved_dat, MAXPGPATH, "%s/%u", moved_tblspc, db_oid); + snprintf(old_dat, sizeof(old_dat), "%s/%u", old_tblspc, db_oid); + + /* Check that the database directory exists in the given tablespace. */ + if (stat(old_dat, &st) != 0) + { + if (errno != ENOENT) + pg_fatal("could not stat file \"%s\": %m", old_dat); + return false; + } + + /* Create directory for stuff that is moved aside. */ + if (pg_mkdir_p(moved_tblspc, pg_dir_create_mode) != 0 && errno != EEXIST) + pg_fatal("could not create directory \"%s\"", moved_tblspc); + + /* Create directory for old catalog files. */ + if (pg_mkdir_p(old_cat, pg_dir_create_mode) != 0) + pg_fatal("could not create directory \"%s\"", old_cat); + + /* Move the new cluster's database directory aside. */ + if (rename(new_dat, moved_dat) != 0) + pg_fatal("could not rename \"%s\" to \"%s\"", new_dat, moved_dat); + + /* Move the old cluster's database directory into place. */ + if (rename(old_dat, new_dat) != 0) + pg_fatal("could not rename \"%s\" to \"%s\"", old_dat, new_dat); + + return true; +} + +/* + * FileNameMapCmp() + * + * qsort() comparator for FileNameMap that sorts by RelFileNumber. + */ +static int +FileNameMapCmp(const void *a, const void *b) +{ + const FileNameMap *map1 = (const FileNameMap *) a; + const FileNameMap *map2 = (const FileNameMap *) b; + + return pg_cmp_u32(map1->relfilenumber, map2->relfilenumber); +} + +/* + * parse_relfilenumber() + * + * Attempt to parse the RelFileNumber of the given file name. If we can't, + * return InvalidRelFileNumber. + */ +static RelFileNumber +parse_relfilenumber(const char *filename) +{ + char *endp; + unsigned long n; + + if (filename[0] < '1' || filename[0] > '9') + return InvalidRelFileNumber; + + errno = 0; + n = strtoul(filename, &endp, 10); + if (errno || filename == endp || n <= 0 || n > PG_UINT32_MAX) + return InvalidRelFileNumber; + + return (RelFileNumber) n; +} + +/* + * swap_catalog_files() + * + * Moves the old catalog files aside, and moves the new catalog files into + * place. + */ +static void +swap_catalog_files(FileNameMap *maps, int size, const char *old_cat, + const char *new_dat, const char *moved_dat) +{ + DIR *dir; + struct dirent *de; + char path[MAXPGPATH]; + char dest[MAXPGPATH]; + RelFileNumber rfn; + + /* Move the old catalog files aside. */ + dir = opendir(new_dat); + if (dir == NULL) + pg_fatal("could not open directory \"%s\": %m", new_dat); + while (errno = 0, (de = readdir(dir)) != NULL) + { + if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0) + continue; + + snprintf(path, sizeof(path), "%s/%s", new_dat, de->d_name); + if (get_dirent_type(path, de, false, PG_LOG_ERROR) != PGFILETYPE_REG) + continue; + + rfn = parse_relfilenumber(de->d_name); + if (RelFileNumberIsValid(rfn)) + { + FileNameMap key = {.relfilenumber = rfn}; + + if (bsearch(&key, maps, size, sizeof(FileNameMap), FileNameMapCmp)) + continue; + } + + snprintf(dest, sizeof(dest), "%s/%s", old_cat, de->d_name); + if (rename(path, dest) != 0) + pg_fatal("could not rename \"%s\" to \"%s\": %m", path, dest); + } + + if (errno) + pg_fatal("could not read directory \"%s\": %m", new_dat); + (void) closedir(dir); + + /* Move the new catalog files into place. */ + dir = opendir(moved_dat); + if (dir == NULL) + pg_fatal("could not open directory \"%s\": %m", moved_dat); + while (errno = 0, (de = readdir(dir)) != NULL) + { + if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0) + continue; + + snprintf(path, sizeof(path), "%s/%s", moved_dat, de->d_name); + if (get_dirent_type(path, de, false, PG_LOG_ERROR) != PGFILETYPE_REG) + continue; + + rfn = parse_relfilenumber(de->d_name); + if (RelFileNumberIsValid(rfn)) + { + FileNameMap key = {.relfilenumber = rfn}; + + if (bsearch(&key, maps, size, sizeof(FileNameMap), FileNameMapCmp)) + continue; + } + + snprintf(dest, sizeof(dest), "%s/%s", new_dat, de->d_name); + if (rename(path, dest) != 0) + pg_fatal("could not rename \"%s\" to \"%s\": %m", path, dest); + + /* + * We don't fsync() the database files in the file synchronization + * stage of pg_upgrade in swap mode, so we need to synchronize them + * ourselves. We only do this for the catalog files because they were + * created during pg_restore with fsync=off. We assume that the user + * data files files were properly persisted to disk when the user last + * shut it down. + */ + sync_queue_push(dest); + } + + if (errno) + pg_fatal("could not read directory \"%s\": %m", moved_dat); + (void) closedir(dir); + + /* Ensure the directory entries are persisted to disk. */ + if (fsync_fname(new_dat, true) != 0) + pg_fatal("could not synchronize directory \"%s\": %m", new_dat); + if (fsync_parent_path(new_dat) != 0) + pg_fatal("could not synchronize parent directory of \"%s\": %m", new_dat); +} + +/* + * do_swap() + * + * Perform the required steps for --swap for a single database. In short this + * moves the old cluster's database directory into the new cluster and then + * replaces any files for system catalogs with the ones that were generated + * during pg_restore. + */ +static void +do_swap(FileNameMap *maps, int size, char *old_tablespace) +{ + char old_cat[MAXPGPATH]; + char new_dat[MAXPGPATH]; + char moved_dat[MAXPGPATH]; + + /* + * We perform many lookups on maps by relfilenumber in swap mode, so make + * sure it's sorted. + */ + qsort(maps, size, sizeof(FileNameMap), FileNameMapCmp); + + /* + * If an old tablespace is given, we only need to process that one. If no + * old tablespace is specified, we need to process all the tablespaces on + * the system. + */ + if (old_tablespace) + { + if (prepare_for_swap(old_tablespace, maps[0].db_oid, + old_cat, new_dat, moved_dat)) + swap_catalog_files(maps, size, old_cat, new_dat, moved_dat); + } + else + { + if (prepare_for_swap(old_cluster.pgdata, maps[0].db_oid, + old_cat, new_dat, moved_dat)) + swap_catalog_files(maps, size, old_cat, new_dat, moved_dat); + + for (int tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++) + { + if (prepare_for_swap(os_info.old_tablespaces[tblnum], maps[0].db_oid, + old_cat, new_dat, moved_dat)) + swap_catalog_files(maps, size, old_cat, new_dat, moved_dat); + } + } } /* @@ -145,6 +484,20 @@ transfer_single_new_db(FileNameMap *maps, int size, char *old_tablespace) new_cluster.controldata.cat_ver >= VISIBILITY_MAP_FROZEN_BIT_CAT_VER) vm_must_add_frozenbit = true; + /* --swap has its own subroutine */ + if (user_opts.transfer_mode == TRANSFER_MODE_SWAP) + { + /* + * We don't support --swap to upgrade from versions that require + * rewriting the visibility map. We should've failed already if + * someone tries to do that. + */ + Assert(!vm_must_add_frozenbit); + + do_swap(maps, size, old_tablespace); + return; + } + for (mapnum = 0; mapnum < size; mapnum++) { if (old_tablespace == NULL || @@ -259,6 +612,11 @@ transfer_relfile(FileNameMap *map, const char *type_suffix, bool vm_must_add_fro pg_log(PG_VERBOSE, "linking \"%s\" to \"%s\"", old_file, new_file); linkFile(old_file, new_file, map->nspname, map->relname); + break; + case TRANSFER_MODE_SWAP: + /* swap mode is handled in its own code path */ + pg_fatal("should never happen"); + break; } } } diff --git a/src/common/file_utils.c b/src/common/file_utils.c index 78e272916f5..4405ef8b425 100644 --- a/src/common/file_utils.c +++ b/src/common/file_utils.c @@ -45,9 +45,6 @@ */ #define MINIMUM_VERSION_FOR_PG_WAL 100000 -#ifdef PG_FLUSH_DATA_WORKS -static int pre_sync_fname(const char *fname, bool isdir); -#endif static void walkdir(const char *path, int (*action) (const char *fname, bool isdir), bool process_symlinks, @@ -352,16 +349,16 @@ walkdir(const char *path, } /* - * Hint to the OS that it should get ready to fsync() this file. + * Hint to the OS that it should get ready to fsync() this file, if supported + * by the platform. * * Ignores errors trying to open unreadable files, and reports other errors * non-fatally. */ -#ifdef PG_FLUSH_DATA_WORKS - -static int +int pre_sync_fname(const char *fname, bool isdir) { +#ifdef PG_FLUSH_DATA_WORKS int fd; fd = open(fname, O_RDONLY | PG_BINARY, 0); @@ -388,11 +385,10 @@ pre_sync_fname(const char *fname, bool isdir) #endif (void) close(fd); +#endif /* PG_FLUSH_DATA_WORKS */ return 0; } -#endif /* PG_FLUSH_DATA_WORKS */ - /* * fsync_fname -- Try to fsync a file or directory * diff --git a/src/include/common/file_utils.h b/src/include/common/file_utils.h index 8274bc877ab..9fd88953e43 100644 --- a/src/include/common/file_utils.h +++ b/src/include/common/file_utils.h @@ -33,6 +33,7 @@ typedef enum DataDirSyncMethod struct iovec; /* avoid including port/pg_iovec.h here */ #ifdef FRONTEND +extern int pre_sync_fname(const char *fname, bool isdir); extern int fsync_fname(const char *fname, bool isdir); extern void sync_pgdata(const char *pg_data, int serverVersion, DataDirSyncMethod sync_method, bool sync_data_files); -- 2.39.5 (Apple Git-154)
