With regards to your message at 11:04 PM 2/23/03, Neil Brown. Where you stated:
> If this is even something doable (tweakable) Im wondering what the perf > gain from allocating say 2 or 4gb just to raid cache would be. > > Comments ? How do you imagine this extra 'cache' would be used. Cache on raid cards tends to be battery backed (I believe) and to operate as a write-behind cache thereby increasing performance. As main system memory is not battery backed, you cannot use it as a write-behind cache. NeilBrown
True, and the cache on a RAID controller is not clobbered when the OS or computer crashes.
Mind you the same problem exists to some degree with PCI based RAID controllers, so the most robust are host independent SCSI/SCSI RAID controllers.
Too bad these cost about as much as a typical server!
With our best regards,
Maurice W. Hilarius Telephone: 01-780-456-9771
Hard Data Ltd. FAX: 01-780-456-9772
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Edmonton, AB, Canada http://www.harddata.com/
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