Merlin Moncure wrote: > > although for postgres the thing that you are doing the fsync on is the WAL > > log file. that is a single (usually) contiguous file. As such it is very > > efficiant to write large chunks of it. so while you will degrade from the > > battery-only mode, the fact that the controller can flush many requests > > worth of writes out to the WAL log at once while you fill the cache with > > them one at a time is still a significant win. > > The heap files have to be synced as well during checkpoints, etc. True, but as of 8.3 those checkpoint fsyncs are spread over the interval between checkpoints. -- Bruce Momjian <bruce@xxxxxxxxxx> http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. +
