From a6d033aff90a6218345cba41847ccfdfbe6447d7 Mon Sep 17 00:00:00 2001 From: Nathan Bossart Date: Mon, 21 Feb 2022 16:29:14 -0800 Subject: [PATCH v1 1/1] remove more archiving overhead --- src/backend/access/transam/xlogarchive.c | 15 +++++++++++++-- src/backend/postmaster/pgarch.c | 13 ++++++++++++- 2 files changed, 25 insertions(+), 3 deletions(-) diff --git a/src/backend/access/transam/xlogarchive.c b/src/backend/access/transam/xlogarchive.c index a2657a2005..d6823c9c38 100644 --- a/src/backend/access/transam/xlogarchive.c +++ b/src/backend/access/transam/xlogarchive.c @@ -585,8 +585,13 @@ XLogArchiveForceDone(const char *xlog) * If it is not time to delete it, make sure a .ready file exists, and return * false. * - * If .done exists, then return true; else if .ready exists, - * then return false; else create .ready and return false. + * If .done exists, then sync the archive_status directory to disk and + * return true. Syncing the directory ensures that the rename from + * .ready to .done is persisted so that we won't attempt to re- + * archive the file after a crash. + * + * If .ready exists, then return false. If neither .ready nor + * .done exist, create .ready and return false. * * The reason we do things this way is so that if the original attempt to * create .ready fails, we'll retry during subsequent checkpoints. @@ -618,7 +623,10 @@ XLogArchiveCheckDone(const char *xlog) /* First check for .done --- this means archiver is done with it */ StatusFilePath(archiveStatusPath, xlog, ".done"); if (stat(archiveStatusPath, &stat_buf) == 0) + { + fsync_fname(XLOGDIR "/archive_status", true); return true; + } /* check for .ready --- this means archiver is still busy with it */ StatusFilePath(archiveStatusPath, xlog, ".ready"); @@ -628,7 +636,10 @@ XLogArchiveCheckDone(const char *xlog) /* Race condition --- maybe archiver just finished, so recheck */ StatusFilePath(archiveStatusPath, xlog, ".done"); if (stat(archiveStatusPath, &stat_buf) == 0) + { + fsync_fname(XLOGDIR "/archive_status", true); return true; + } /* Retry creation of the .ready file */ XLogArchiveNotify(xlog); diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c index d916ed39a8..44cb58e1f4 100644 --- a/src/backend/postmaster/pgarch.c +++ b/src/backend/postmaster/pgarch.c @@ -746,7 +746,18 @@ pgarch_archiveDone(char *xlog) StatusFilePath(rlogready, xlog, ".ready"); StatusFilePath(rlogdone, xlog, ".done"); - (void) durable_rename(rlogready, rlogdone, WARNING); + + /* + * To reduce overhead, we don't durably rename the .ready file to .done + * here. Whoever recycles or removes the WAL file is responsible for first + * persisting the archive_status directory to disk so that we won't attempt + * to re-archive the file after a crash. + */ + if (rename(rlogready, rlogdone) < 0) + ereport(WARNING, + (errcode_for_file_access(), + errmsg("could not rename file \"%s\" to \"%s\": %m", + rlogready, rlogdone))); } -- 2.25.1