Kevin Grittner wrote: > Bruce Momjian <bruce@xxxxxxxxxx> wrote: > > > On another topic, I am a little unclear on how things behave when > > the drive is write-back. If the RAID controller card writes to the > > drive, but the data isn't on the platers, how does it know when it > > can discard that information from the BBU RAID cache? > > The controller waits for the drive to tell it that it has made it to > the platter before it discards it. What made you think otherwise? Because a write-back drive cache says it is on the drive before it hits the platters, which I think is the default for SATA drive. Is that inaccurate? -- Bruce Momjian <bruce@xxxxxxxxxx> http://momjian.us EnterpriseDB http://enterprisedb.com + None of us is going to be here forever. + -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
