Thank you for sugestion. > This still makes catching up in standby mode slower, as you get > many more restartpoints. The reason for ignoring > checkpoint_segments during recovery was to avoid that.
I may have a misunderstanding around there, or your intention. I understand that standby creates no WAL archive, and can not recover from WAL archive, and both master and standby keeps WAL segment no longer than about them for about 2 * 1h, spans two maximum checkpoint_timeout intervals and some more. Could you please tell me whether the above is correct? If you meant crash recovery with the word 'recovery', there's WALs no more than for 2+ hours, far less than days, or weeks long. Otherwise, if you meant archive recovery, this patch does not change the behavior of archive recovery as far as I intended. This patch intended to change the behavior of standby under WAL shipping. If it is correct and the patch works correctly, your anxiety below should disappear, I hope. And if not correct, I *MUST* avoid such negative impacts on the functions out of the target - governing checkpoint progress on standby server shipping WALs from its master. > Maybe it's still better than what we have currently, I'm not > sure, but at least it needs to be discussed. Would be good to > do some performance testing of recovery with various > checkpoint_segments and _timeout settings, with and without > this patch. regards, -- Kyotaro Horiguchi NTT Open Source Software Center == My e-mail address has been changed since Apr. 1, 2012. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
