On 8 June 2012 15:21, Robert Haas <robertmh...@gmail.com> wrote: > On Fri, Jun 8, 2012 at 9:58 AM, Simon Riggs <si...@2ndquadrant.com> wrote: >> On 8 June 2012 14:47, Robert Haas <robertmh...@gmail.com> wrote: >> >>>> ISTM that we should avoid triggering a checkpoint on the master if >>>> checkpoint_segments is less than wal_keep_segments. Such checkpoints >>>> serve no purpose because we don't actually limit and recycle the WAL >>>> files and all it does is slow people down. >>> >>> On the other hand, I emphatically disagree with this, for the same >>> reasons as on the other thread. Getting data down to disk provides a >>> greater measure of safety than having it in memory. Making >>> checkpoint_segments not force a checkpoint is no better than making >>> checkpoint_timeout not force a checkpoint. >> >> Not sure which bit you are disagreeing with. I have no suggested >> change to checkpoint_timeout. > > You already made it not a hard timeout. We have another nearby thread > discussing why I don't like that. > >> What I'm saying is that forcing a checkpoint to save space, when we >> aren't going to save space, makes no sense. > > We are also forcing a checkpoint to limit recovery time and data loss > potential, not just to save space.
Nothing I've said on this thread is related to the other thread. Please don't confuse matters. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
