At Wed, 30 Jan 2019 15:53:51 +0000, [email protected] wrote in
<[email protected]>
> Hi
> I have reported a bug via PostgreSQL bug report form, but havent got any
> response so far.
> This might not be a bug, but a feature not implemented yet.
> I suggest to make a small addition to StartupXLOG to solve the issue.
I can understand what you want, but it doesn't seem acceptable
since it introduces inconsistency among target kinds.
> The scenario I want to solve is:
> Need to restore backup to another server.
> Restores pgbasebackup files
> Restores som wal-files
> Extract pgbasebackup files
> creates recover.conf with pit
> Starts postgresql
> recover ends before pit due to missing wal-files
> database opens read/write
>
> I think database should have paused recovery then I could restore
> additional wal-files and restart postgresql to continue with recover.
I don't think no one expected that server follows
recovery_target_action without setting a target, so we can change
the behavior when any kind of target is specified. So I propose
to follow recovery_target_action even if not rached the target
when any recovery target isspecified.
With the attached PoC (for master), recovery stops as follows:
LOG: consistent recovery state reached at 0/2F000000
LOG: database system is ready to accept read only connections
rc_work/00000001000000000000002F’: No such file or directory
WARNING: not reached specfied recovery target, take specified action anyway
DETAIL: This means a wrong target or missing of expected WAL files.
LOG: recovery has paused
HINT: Execute pg_wal_replay_resume() to continue.
If no target is specifed, it promtes immediately ignoring r_t_action.
If this is acceptable I'll post complete version (including
documentation). I don't think this back-patcheable.
> With large databases and a lot of wal-files it is time consuming to repeat
> parts of the process.
I understand your concern.
regards.
--
Kyotaro Horiguchi
NTT Open Source Software Center
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 2ab7d804f0..081bdd86ec 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7246,12 +7246,25 @@ StartupXLOG(void)
* end of main redo apply loop
*/
- if (reachedStopPoint)
+ /*
+ * If recovery target is specified, specified action is expected
+ * to be taken regardless whether the target is reached or not .
+ */
+ if (recoveryTarget != RECOVERY_TARGET_UNSET)
{
+ /*
+ * At this point we don't consider the case where we are
+ * before consistent point even if not reached stop point.
+ */
if (!reachedConsistency)
ereport(FATAL,
(errmsg("requested recovery stop point is before consistent recovery point")));
+ if (!reachedStopPoint)
+ ereport(WARNING,
+ (errmsg ("not yet reached specfied recovery target, take specified action anyway"),
+ errdetail("This means a wrong target or missing WAL files.")));
+
/*
* This is the last point where we can restart recovery with a
* new recovery target, if we shutdown and begin again. After
