All,
Was that sequential reads? If so, yeah you'll get 110MB/s? How big
was the datafile size? 8MB? Yeah, you'll get 110MB/s. 2GB? No, they
can't sustain that. There are so many details missing from this test
that it's hard to have any context around it :)
I was getting about 40-50MB/s on a PV with 14 disks on a RAID10 in
real world usage. (random IO and fully saturating a Dell 1850 with 4
concurrent threads (to peg the cpu on selects) and raw data files)
Best Regards,
Dan Gorman
On Feb 24, 2006, at 4:29 PM, Mark Kirkwood wrote:
Luke Lonergan wrote:
I'd be more shocked if this weren't also true of nearly all SCSI
HW RAID
adapters of this era. If you had ordered an HP DL380 server you'd
get about
the same performance.
BTW - I don't think there's anything reasonable about 50-55 MB/s
from 6
disks, I'd put the minimum for this era machine at 5 x 30 = 150MB/s.
He was quoting for 6 disk RAID 10 - I'm thinking 3 x 30MB/s = 90MB/
s is probably more correct? Having aid that, your point is still
completely correct - the performance @55MB/s is poor (e.g. my *ata*
system with 2 disk RAID0 does reads @110MB/s).
cheers
Mark
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