questions about a PERC in a 2950

J. Epperson Dell at epperson.homelinux.net
Mon Oct 22 17:17:32 CDT 2007


On Mon, October 22, 2007 05:00, Marcus Bointon wrote:
>
> On 21 Oct 2007, at 08:18, Kuba Ober wrote:
>
>>> The big advantage of hardware RAID is the hardware battery-backed RAM
>>>  cache that is on the card.
>>>
>>> I find this piece of hardware essential for both performance (it
>>> absorbs disk flush gracefully)
>>
>> Seems to be a non-argument. You imply that your OS is 256MB (or
>> whatever) short on buffer memory. That's an easy fix, doesn't require a
>> RAID controller ;)
>
> Huh? For performance maybe, but there is no possible software equivalent
> to battery backed cache. If you cache writes in normal RAM and pull the
> plug, your data is gone, end of story.
>

And if you need RAID and aren't using and regularly testing a UPS, you
deserve it.  I'm on the hardware RAID side of this discussion, but fair is
fair.



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