Re: time-delayed standbys
Fujii Masao <masao.fujii@gmail.com>
From: Fujii Masao <masao.fujii@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Greg Stark <gsstark@mit.edu>, pgsql-hackers@postgresql.org
Date: 2011-06-20T01:57:28Z
Lists: pgsql-hackers
On Fri, Jun 17, 2011 at 11:34 AM, Robert Haas <robertmhaas@gmail.com> wrote: > On Thu, Jun 16, 2011 at 10:10 PM, Fujii Masao <masao.fujii@gmail.com> wrote: >>>> According to the above page, one purpose of time-delayed replication is to >>>> protect against user mistakes on master. But, when an user notices his wrong >>>> operation on master, what should he do next? The WAL records of his wrong >>>> operation might have already arrived at the standby, so neither "promote" nor >>>> "restart" doesn't cancel that wrong operation. Instead, probably he should >>>> shutdown the standby, investigate the timestamp of XID of the operation >>>> he'd like to cancel, set recovery_target_time and restart the standby. >>>> Something like this procedures should be documented? Or, we should >>>> implement new "promote" mode which finishes a recovery as soon as >>>> "promote" is requested (i.e., not replay all the available WAL records)? >>> >>> I like the idea of a new promote mode; >> >> Are you going to implement that mode in this CF? or next one? > > I wasn't really planning on it - I thought you might want to take a > crack at it. The feature is usable without that, just maybe a bit > less cool. Right. > Certainly, it's too late for any more formal submissions > to this CF, but I wouldn't mind reviewing a patch if you want to write > one. Okay, I add that into my TODO list. But I might not have enough time to develop that. So, everyone, please feel free to implement that if you want! Regards, -- Fujii Masao NIPPON TELEGRAPH AND TELEPHONE CORPORATION NTT Open Source Software Center