Wes Williams writes:
>Even with a primary UPS on the *entire PostgreSQL server* does one still
>need, or even still recommend, a battery-backed cache on the RAID controller
>card? [ref SCSI 320, of course]
>If so, I'd be interest in knowing briefly why.
it can be a lot faster.
if the raid controller knows it has a battery backup, then it'll be free
to do whatever it sees fit in terms of write order.
some controllers (the ibm serveraid 4 units that i have a couple of, for
example) won't do this unless they know the battery is there, they have no
option for overriding that setting.
richard
