Raid 5 on the 9550SX is supposed to be significantly better than the 9500 series.
I would be carefull of benchmarks listed out there. For instance, whilst looking for supporting material, I came cross this gem:
http://www.gamepc.com/labs/print_content.asp?id=9550sx4lp&cookie%5Ftest=1 They claim the they used a Tyan Thunder K8WE motherboard, and installed the RAID controllers in a 64-bit 133MHz PCI-X slot. This motherboard doesn't have any 64-bit 133Mhz PCI-X slots! (
http://www.tyan.com/products/html/tigerk8we_spec.html).
It's no wonder that the other raid controllers showed significantly less performance than the PCI-e card.
This review from tomshardware:
http://www.tomshardware.com/2005/10/31/sata_spells_trouble_for_scsi_raid/page13.html Suggests that the 9550SX is at least competitive with the others.
I know I like the 3ware/AMCC cards because of their very good RAID 10 performance. I'm not a big RAID 5 fan. RAID 5 sufferes the read before write penalty problem that make RAID 5 writes very slow, particularly noticebale in OLTP applications. RAID 10 will almost always offer better write perfomance.
I wish we could set up an organization to do benchmarks with pgbench on various different RAID controllers/drives and publish the results. I know I would pay money for that.
Alex
On 4/15/06, Francisco Reyes <lists@stringsutils.com > wrote: Merlin Moncure writes:
> escalade is a fairly full featured raid controller for the price.
> consider it the ford taurus of raid controllers, it's functional and
> practical but not sexy. Their S line is not native sata but operates
> over a pata->sata bridge. Stay away from raid 5.
Do you know if their raid 5 is better in the new 9550SX?
Or is the "Stay away from raid 5" more of a general comment that this type
of raid is not good for DBs?
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