[dm-devel] Re: [Consult-list] dm-multipath has great throughput but we'd like more!

[Luca Berra]

On Thu, May 18, 2006 at 02:36:00AM -0500, Jonathan E Brassow wrote:
>
>On May 18, 2006, at 2:27 AM, Luca Berra wrote:
>
>>On Thu, May 18, 2006 at 08:19:09AM +0100, Bob Gautier wrote:
>>>On Thu, 2006-05-18 at 08:05 +0100, Bob Gautier wrote:
>>>>Yesterday my client was testing of multipath load balancing and 
>>>>failover
>>>>on a system running ext3 on a logical volume which comprises about 
>>>>ten
>>>>SAN LUNs all reached using multipath in multibus mode over two QL2340
>>>>HBAs.
>>>
>>>Sorry, should have also said: RHEL4u3 x86_64 on DL385 with 16Gb memory
>>>
>>you could have added the storage model :)
>>btw did you do any tuning (i.e. readhaead, scheduler) ?
>>
>
>You may also want to do raw through-put testing (lmdd perhaps) to get a 
>baseline.  Certainly, the file system has to be bringing down the 
>bandwidth somewhat...
>
in some cases even the partition alignment might introduce delays.

L.

-- 
Luca Berra -- bluca at comedia.it
        Communication Media & Services S.r.l.
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