>>>I've heard that it is important to disable disk caching on the faster drives. Is that correct?
>>
>>Where did you hear that? Disabling disk cache WILL decrease performance A LOT. That defeats the purpose of 15K drives.
>
>Might have been in discussions on ***other*** back ends, as non-battery-backed caching might make data less ACID-safe.
>>
>>>We're having difficulty turning off the cache on one of the machines and our hardware guy wants to make sure this is what we want.
>>
>>And rightfully so. Bear in mind that sometimes high-performance drives are attached to controllers that implement a cache in hardware, and which can't be turned off.
>
>But there the better ones *are* not prone to lose data on the flip of a switch ;-)

Battery-backed caching controllers have always struck me as a little redundant. If you've got enough UPS to ensure an orderly shutdown, why would they be necessary?