Make WAL-related utilities handle .partial WAL files properly.

Commit de76884 changed an archive recovery so that the last WAL
segment with old timeline was renamed with suffix .partial. It should
have updated WAL-related utilities so that they can handle such
.paritial WAL files, but we forgot that.

This patch changes pg_archivecleanup so that it can clean up even
archived WAL files with .partial suffix. Also it allows us to specify
.partial WAL file name as the command-line argument "oldestkeptwalfile".

This patch also changes pg_resetxlog so that it can remove .partial
WAL files in pg_xlog directory.

pg_xlogdump cannot handle .partial WAL files. Per discussion,
we decided only to document that limitation instead of adding the fix.
Because a user can easily work around the limitation (i.e., just remove
.partial suffix from the file name) and the fix seems complicated for
very narrow use case.

Back-patch to 9.5 where the problem existed.

Review by Michael Paquier.
Discussion: http://www.postgresql.org/message-id/CAHGQGwGxMKnVHGgTfiig2Bt_2djec0in3-DLJmtg7+nEiidFdQ@mail.gmail.com
This commit is contained in:
Fujii Masao 2015-07-03 11:53:58 +09:00
parent 5671aaca87
commit 8650d161ae
4 changed files with 43 additions and 10 deletions

View File

@ -215,6 +215,12 @@ PostgreSQL documentation
Only the specified timeline is displayed (or the default, if none is
specified). Records in other timelines are ignored.
</para>
<para>
<application>pg_xlogdump</> cannot read WAL files with suffix
<literal>.partial</>. If those files need to be read, <literal>.partial</>
suffix needs to be removed from the filename.
</para>
</refsect1>
<refsect1>

View File

@ -60,8 +60,10 @@ archive_cleanup_command = 'pg_archivecleanup <replaceable>archivelocation</> %r'
<para>
When used as a standalone program all WAL files logically preceding the
<replaceable>oldestkeptwalfile</> will be removed from <replaceable>archivelocation</>.
In this mode, if you specify a <filename>.backup</> file name, then only the file prefix
will be used as the <replaceable>oldestkeptwalfile</>. This allows you to remove
In this mode, if you specify a <filename>.partial</> or <filename>.backup</>
file name, then only the file prefix will be used as the
<replaceable>oldestkeptwalfile</>. This treatment of <filename>.backup</>
file name allows you to remove
all WAL files archived prior to a specific base backup without error.
For example, the following example will remove all files older than
WAL file name <filename>000000010000003700000010</>:

View File

@ -125,7 +125,7 @@ CleanupPriorWALFiles(void)
* file. Note that this means files are not removed in the order
* they were originally written, in case this worries you.
*/
if (IsXLogFileName(walfile) &&
if ((IsXLogFileName(walfile) || IsPartialXLogFileName(walfile)) &&
strcmp(walfile + 8, exclusiveCleanupFileName + 8) < 0)
{
/*
@ -181,7 +181,7 @@ CleanupPriorWALFiles(void)
* SetWALFileNameForCleanup()
*
* Set the earliest WAL filename that we want to keep on the archive
* and decide whether we need_cleanup
* and decide whether we need cleanup
*/
static void
SetWALFileNameForCleanup(void)
@ -192,9 +192,10 @@ SetWALFileNameForCleanup(void)
/*
* If restartWALFileName is a WAL file name then just use it directly. If
* restartWALFileName is a .backup filename, make sure we use the prefix
* of the filename, otherwise we will remove wrong files since
* 000000010000000000000010.00000020.backup is after
* restartWALFileName is a .partial or .backup filename, make sure we use
* the prefix of the filename, otherwise we will remove wrong files since
* 000000010000000000000010.partial and
* 000000010000000000000010.00000020.backup are after
* 000000010000000000000010.
*/
if (IsXLogFileName(restartWALFileName))
@ -202,6 +203,26 @@ SetWALFileNameForCleanup(void)
strcpy(exclusiveCleanupFileName, restartWALFileName);
fnameOK = true;
}
else if (IsPartialXLogFileName(restartWALFileName))
{
int args;
uint32 tli = 1,
log = 0,
seg = 0;
args = sscanf(restartWALFileName, "%08X%08X%08X.partial",
&tli, &log, &seg);
if (args == 3)
{
fnameOK = true;
/*
* Use just the prefix of the filename, ignore everything after
* first period
*/
XLogFileNameById(exclusiveCleanupFileName, tli, log, seg);
}
}
else if (IsBackupHistoryFileName(restartWALFileName))
{
int args;

View File

@ -906,7 +906,8 @@ FindEndOfXLOG(void)
while (errno = 0, (xlde = readdir(xldir)) != NULL)
{
if (IsXLogFileName(xlde->d_name))
if (IsXLogFileName(xlde->d_name) ||
IsPartialXLogFileName(xlde->d_name))
{
unsigned int tli,
log,
@ -976,7 +977,8 @@ KillExistingXLOG(void)
while (errno = 0, (xlde = readdir(xldir)) != NULL)
{
if (IsXLogFileName(xlde->d_name))
if (IsXLogFileName(xlde->d_name) ||
IsPartialXLogFileName(xlde->d_name))
{
snprintf(path, MAXPGPATH, "%s/%s", XLOGDIR, xlde->d_name);
if (unlink(path) < 0)
@ -1028,7 +1030,9 @@ KillExistingArchiveStatus(void)
{
if (strspn(xlde->d_name, "0123456789ABCDEF") == XLOG_FNAME_LEN &&
(strcmp(xlde->d_name + XLOG_FNAME_LEN, ".ready") == 0 ||
strcmp(xlde->d_name + XLOG_FNAME_LEN, ".done") == 0))
strcmp(xlde->d_name + XLOG_FNAME_LEN, ".done") == 0 ||
strcmp(xlde->d_name + XLOG_FNAME_LEN, ".partial.ready") == 0 ||
strcmp(xlde->d_name + XLOG_FNAME_LEN, ".partial.done") == 0))
{
snprintf(path, MAXPGPATH, "%s/%s", ARCHSTATDIR, xlde->d_name);
if (unlink(path) < 0)