On Sunday 31 October 2010 20:59:31 Greg Smith wrote: > Writes only are sync'd out when you do a commit, or the database does a > checkpoint. Hm? WAL is written out to disk after an the space provided by wal_buffers(def 8) * XLOG_BLCKSZ (def 8192) is used. The default is 64kb which you reach pretty quickly - especially after a checkpoint. With O_D?SYNC that will synchronously get written out during a normal XLogInsert if hits a page boundary. *Additionally* its gets written out at a commit if sync commit is not on. Not having a real O_DSYNC on linux until recently makes it even more dubious to have it as a default... Andres -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
