Re: SSD + RAID
Bruce Momjian <bruce@momjian.us>
From: Bruce Momjian <bruce@momjian.us>
To: Greg Smith <greg@2ndquadrant.com>
Cc: Merlin Moncure <mmoncure@gmail.com>, Brad Nicholson <bnichols@ca.afilias.info>, Karl Denninger <karl@denninger.net>, Laszlo Nagy <gandalf@shopzeus.com>, pgsql-performance <pgsql-performance@postgresql.org>
Date: 2009-11-28T16:20:56Z
Lists: pgsql-performance
Attachments
- /rtmp/diff (text/x-diff) patch
Greg Smith wrote: > Merlin Moncure wrote: > > I am right now talking to someone on postgresql irc who is measuring > > 15k iops from x25-e and no data loss following power plug test. > The funny thing about Murphy is that he doesn't visit when things are > quiet. It's quite possible the window for data loss on the drive is > very small. Maybe you only see it one out of 10 pulls with a very > aggressive database-oriented write test. Whatever the odd conditions > are, you can be sure you'll see them when there's a bad outage in actual > production though. > > A good test program that is a bit better at introducing and detecting > the write cache issue is described at > http://brad.livejournal.com/2116715.html Wow, I had not seen that tool before. I have added a link to it from our documentation, and also added a mention of our src/tools/fsync test tool to our docs. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. +