Re: Reliability recommendations

[Dan Gorman <dgorman(at)hi5(dot)com>]

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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