Re: no universally correct setting for fsync
Yeb Havinga <yebhavinga@gmail.com>
From: Yeb Havinga <yebhavinga@gmail.com>
To: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: jd@commandprompt.com, Greg Stark <gsstark@mit.edu>, Robert Haas <robertmhaas@gmail.com>, Bruce Momjian <bruce@momjian.us>, Michael Tharp <gxti@partiallystapled.com>, pgsql-hackers@postgresql.org, Craig Ringer <craig@postnewspapers.com.au>
Date: 2010-05-11T08:00:21Z
Lists: pgsql-hackers
Kevin Grittner wrote: > "Joshua D. Drake" <jd@commandprompt.com> wrote: > > >> The answer to this is: >> >> PostgreSQL.org recommends that this setting be left on at all >> times. Turning it off, may lead to data corruption. >> >> Anything else is circumstantial and based on knowledge and facts >> we don't have about environmental factors. >> > > Perhaps Josh's language for fsync could be modified to work here > (we're now talking about full_page_writes, for anyone who's lost > track): > > | it is only advisable to turn off fsync if you can easily recreate > | your entire database from external data. > > That covers bulk loads to an empty or just-backed-up database and > entirely redundant databases. Saying it should never be turned off > would tend to make one wonder why we have the setting at all. > Would the term "entirely redundant databases" include (synchronously) replicated databases? (ps: I did indeed lose track about whether this is about fsync or full_page_writes and did not get on the track again) regards, Yeb Havinga