diff options
| -rw-r--r-- | src/backend/postmaster/pgarch.c | 72 |
1 files changed, 46 insertions, 26 deletions
diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c index e88d545d65b..5c1a577dd4b 100644 --- a/src/backend/postmaster/pgarch.c +++ b/src/backend/postmaster/pgarch.c @@ -695,11 +695,12 @@ pgarch_archiveXlog(char *xlog) * 2) because the oldest ones will sooner become candidates for * recycling at time of checkpoint * - * NOTE: the "oldest" comparison will presently consider all segments of - * a timeline with a smaller ID to be older than all segments of a timeline - * with a larger ID; the net result being that past timelines are given - * higher priority for archiving. This seems okay, or at least not - * obviously worth changing. + * NOTE: the "oldest" comparison will consider any .history file to be older + * than any other file except another .history file. Segments on a timeline + * with a smaller ID will be older than all segments on a timeline with a + * larger ID; the net result being that past timelines are given higher + * priority for archiving. This seems okay, or at least not obviously worth + * changing. */ static bool pgarch_readyXlog(char *xlog) @@ -711,10 +712,10 @@ pgarch_readyXlog(char *xlog) * of calls, so.... */ char XLogArchiveStatusDir[MAXPGPATH]; - char newxlog[MAX_XFN_CHARS + 6 + 1]; DIR *rldir; struct dirent *rlde; bool found = false; + bool historyFound = false; snprintf(XLogArchiveStatusDir, MAXPGPATH, XLOGDIR "/archive_status"); rldir = AllocateDir(XLogArchiveStatusDir); @@ -722,32 +723,51 @@ pgarch_readyXlog(char *xlog) while ((rlde = ReadDir(rldir, XLogArchiveStatusDir)) != NULL) { int basenamelen = (int) strlen(rlde->d_name) - 6; + char basename[MAX_XFN_CHARS + 1]; + bool ishistory; - if (basenamelen >= MIN_XFN_CHARS && - basenamelen <= MAX_XFN_CHARS && - strspn(rlde->d_name, VALID_XFN_CHARS) >= basenamelen && - strcmp(rlde->d_name + basenamelen, ".ready") == 0) + /* Ignore entries with unexpected number of characters */ + if (basenamelen < MIN_XFN_CHARS || + basenamelen > MAX_XFN_CHARS) + continue; + + /* Ignore entries with unexpected characters */ + if (strspn(rlde->d_name, VALID_XFN_CHARS) < basenamelen) + continue; + + /* Ignore anything not suffixed with .ready */ + if (strcmp(rlde->d_name + basenamelen, ".ready") != 0) + continue; + + /* Truncate off the .ready */ + memcpy(basename, rlde->d_name, basenamelen); + basename[basenamelen] = '\0'; + + /* Is this a history file? */ + ishistory = IsTLHistoryFileName(basename); + + /* + * Consume the file to archive. History files have the highest + * priority. If this is the first file or the first history file + * ever, copy it. In the presence of a history file already chosen as + * target, ignore all other files except history files which have been + * generated for an older timeline than what is already chosen as + * target to archive. + */ + if (!found || (ishistory && !historyFound)) { - if (!found) - { - strcpy(newxlog, rlde->d_name); - found = true; - } - else - { - if (strcmp(rlde->d_name, newxlog) < 0) - strcpy(newxlog, rlde->d_name); - } + strcpy(xlog, basename); + found = true; + historyFound = ishistory; + } + else if (ishistory || !historyFound) + { + if (strcmp(basename, xlog) < 0) + strcpy(xlog, basename); } } FreeDir(rldir); - if (found) - { - /* truncate off the .ready */ - newxlog[strlen(newxlog) - 6] = '\0'; - strcpy(xlog, newxlog); - } return found; } |