On Fri, Sep 14, 2012 at 12:21 PM, Amit Kapila <amit.kap...@huawei.com> wrote: > On Thursday, September 13, 2012 10:32 PM Fujii Masao wrote: > On Thu, Sep 13, 2012 at 9:21 PM, Heikki Linnakangas <hlinn...@iki.fi> wrote: >> On 12.09.2012 22:03, Fujii Masao wrote: >>> >>> On Wed, Sep 12, 2012 at 8:47 PM,<amit.kap...@huawei.com> wrote: >>>> >>>> The following bug has been logged on the website: >>>> >>>> Bug reference: 7533 >>>> Logged by: Amit Kapila >>>> Email address: amit.kap...@huawei.com >>>> PostgreSQL version: 9.2.0 >>>> Operating system: Suse >>>> Description: >>>> >>>> M host is primary, S host is standby and CS host is cascaded standby. >>>> >> > > >>> Hmm, I think the CheckRecoveryConsistency() call in the redo loop is >>> misplaced. It's called after we got a record from ReadRecord, but *before* >>> replaying it (rm_redo). Even if replaying record X makes the system >>> consistent, we won't check and notice that until we have fetched record X+1. >>> In this particular test case, record X is a shutdown checkpoint record, but >>> it could as well be a running-xacts record, or the record that reaches >>> minRecoveryPoint. >> >>> Does the problem go away if you just move the CheckRecoveryConsistency() >>> call *after* rm_redo (attached)? > >> No, at least in my case. When recovery starts at shutdown checkpoint record >> and >> there is no record following the shutdown checkpoint, recovery gets in >> wait state >> before entering the main redo apply loop. That is, recovery starts waiting >> for >> new WAL record to arrive, in ReadRecord just before the redo loop. So moving >> the CheckRecoveryConsistency() call after rm_redo cannot fix the problem >> which >>I reported. To fix the problem, we need to make the recovery reach the >> consistent >> point before the redo loop, i.e., in the CheckRecoveryConsistency() >> just before the redo loop. > > I think may be in that case we need both the fixes, as the problem I have > reported can be fixed with Heikki's patch.
Agreed. And we should just add the CheckRecoveryConsistency() call after rm_redo rather than moving it, as you suggested upthread. Regards, -- Fujii Masao -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
