A B wrote:
If I had a controller with battery, then I could use fsync=off, but I should still disable the write cache?
Never turn fsync=off. Always disable any write cache on the drives themselves; most good battery-backed RAID controllers will do that for you. So long as the battery continues to work, you can keep the write cache on the controller itself enabled, and in fact you have to do so in order to get good commit performance. Given that eventually all batteries fail, the better cards on the market actually make that an explicit setting, which is the safest setting if available: write-back cache enabled when battery works, write-through [cache disabled] if doesn't.
Make sure you setup monitoring alerts via e-mail for drive and battery failures too; test them out by yanking at drive before the server goes into production if you can.
-- Greg Smith 2ndQuadrant US Baltimore, MD PostgreSQL Training, Services and Support greg@xxxxxxxxxxxxxxx www.2ndQuadrant.us -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
