Messages in this thread | | | Date | Tue, 17 May 2011 09:20:30 +0200 | From | Jens Axboe <> | Subject | Re: Perfromance drop on SCSI hard disk |
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On 2011-05-17 08:09, Alex,Shi wrote: > On Mon, 2011-05-16 at 16:37 +0800, Alex,Shi wrote: >>>> what I mean is current sdev (other devices too) can still be added into >>>> starved list, so only does async execute for current q isn't enough, >>>> we'd better put whole __scsi_run_queue into workqueue. something like >>>> below on top of yours, untested. Not sure if there are other recursive >>>> cases. >>> verified the regression can be fully fixed by your patch (with my >>> suggested fix to avoid race). Can we put a formal patch upstream? >> >> Yes, we tested Jens patch alone and plus Shaohua's patch too. Both of >> them recovered SAS disk performance too. Now I am testing them on SSD >> disk with kbuild and fio cases, In theory, they will both work. >> > > As expected, both patches has no effect on SSD disks in JBD.
I will queue up the combined patch, it looks fine from here as well.
-- Jens Axboe
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