[CentOS] 3Ware 9550SX and latency/system responsiveness

[Ross S. W. Walker]

Simon Banton wrote:
> 
> At 08:09 -0400 14/9/07, Jim Perrin wrote:
> >Have you done any filesystem optimization and tried matching the
> >filesystem to the raid chunk size?
> 
> No, I haven't. This is 3ware hardware RAID-1 on two disks with a 
> single LVM ext3 / partition - I'm afraid I don't know how to go about 
> discovering the chunk size to plug into Ross's calcs.

I wouldn't worry about calculations at this point. Everything you
described is pointing to bad hardware and not software tuning.

Try getting another identical 3ware card and swapping them. If it
produces the same problem, then try putting that card in another
box with a different motherboard to see if it works then.

Once the basic card is working then we can talk about getting the
maximum performance out of it.

-Ross

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