Messages in this thread | | | Date | Tue, 9 Apr 2013 12:52:59 -0700 | From | Tejun Heo <> | Subject | Re: dm-crypt parallelization patches |
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On Tue, Apr 09, 2013 at 03:42:16PM -0400, Mikulas Patocka wrote: > If I drop ifdefs, it doesn't compile (because other cgroup stuff it > missing). > > So I enabled bio cgroups. > > bio_associate_current can't be used, because by the time we allocate the > outgoing write bio, we are no longer in the process that submitted the > original bio.
Oh, I suppose it'd need some massaging to selectively turn off the cgroup part.
> Anyway, I tried to reproduce in dm-crypt what bio_associate_current does -
and we probably need to change that to bio_associate_task().
> in the submitting process I record "ioc" and "css" fields in "dm_crypt_io" > structure and set these fields on all outgoing bios. It has no effect on > performance, it is as bad as if I hadn't done it.
A good way to verify that the tagging is correct would be configuring io limits in block cgroup and see whether the limits are correctly applied when going through dm-crypt (please test with direct-io or reads, writeback is horribly broken, sorry).working correctly, maybe plugging is the overriding factor?
Thanks.
-- tejun
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