On Tue, 2006-05-09 at 20:02, Bruce Momjian wrote: > Scott Marlowe wrote: > > Actually, in the case of the Escalades at least, the answer is yes. > > Last year (maybe a bit more) someone was testing an IDE escalade > > controller with drives that were known to lie, and it passed the power > > plug pull test repeatedly. Apparently, the escalades tell the drives to > > turn off their cache. While most all IDEs and a fair number of SATA > > drives lie about cache fsyncing, they all seem to turn off the cache > > when you ask. > > > > And, since a hardware RAID controller with bbu cache has its own cache, > > it's not like it really needs the one on the drives anyway. > > You do if the controller thinks the data is already on the drives and > removes it from its cache. Bruce, re-read what I wrote. The escalades tell the drives to TURN OFF THEIR OWN CACHE.