On Sun, Feb 19, 2012 at 5:56 PM, Jeff Janes <jeff.ja...@gmail.com> wrote: > Would the log really have been archived in 9.1? I don't think > checkpoint_timeout caused a log switch, just a checkpoint which could > happily be in the same file as the previous checkpoint.
The log segment doesn't need to get archived - it's sufficient that the dirty buffers get written to disk. >> In 9.2, it may well be that >> xlog contains the only record of that transaction, and you're hosed. >> The more work we do to postpone writing the data until the absolutely >> last possible moment, the more likely it is that it won't be on disk >> when we need it. > > Isn't that what archive_timeut is for? > > Should archive_timeout default to something like 5 min, rather than 0? I dunno. I think people are doing replication are probably mostly using streaming replication these days, in which case archive_timeout won't matter one way or the other. But if you're not doing replication, your only hope of recovering from a trashed pg_xlog is that PostgreSQL wrote the buffers and (in the case of an OS crash) the OS wrote them to disk. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
