From: Alasdair G Kergon <agk@redhat.com>
To: Andi Kleen <andi@firstfloor.org>
Cc: Milan Broz <mbroz@redhat.com>, Mike Snitzer <snitzer@redhat.com>,
Andi Kleen <ak@linux.intel.com>,
device-mapper development <dm-devel@redhat.com>,
pedrib@gmail.com, linux-kernel@vger.kernel.org
Subject: Re: [dm-devel] DM-CRYPT: Scale to multiple CPUs v3
Date: Sun, 10 Oct 2010 20:07:34 +0100 [thread overview]
Message-ID: <20101010190734.GH28828@agk-dp.fab.redhat.com> (raw)
In-Reply-To: <20101010185100.GB21681@basil.fritz.box>
> > AFAIK Nested dm-crypt is not extreme for some folk who have routine
> > configurations using it. But if in_interrupt is set how does this code
^^^^^^^^^^^
> > work for them now compared to how it worked before?
On Sun, Oct 10, 2010 at 08:51:00PM +0200, Andi Kleen wrote:
> Previously they will all pile up on the single worker thread.
> Now in the nested case the nested work is run in their own
> context. This should actually scale better because you
> get parallelism too, not contention on a single resource.
Not if in_interrupt is set though?
+ if (per_cpu(io_wq_cpu, cpu) == current && !in_interrupt()) {
What I am missing here?
(And assume there is only 1 CPU too for worst case behaviour, presumably.)
Alasdair
next prev parent reply other threads:[~2010-10-10 19:07 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-10-10 11:59 [PATCH] DM-CRYPT: Scale to multiple CPUs v3 Andi Kleen
2010-10-10 12:38 ` [dm-devel] " Milan Broz
2010-10-10 12:53 ` Milan Broz
2010-10-10 13:09 ` Andi Kleen
2010-10-10 13:08 ` Andi Kleen
2010-10-10 15:34 ` Milan Broz
2010-10-10 16:06 ` Andi Kleen
2010-10-10 16:22 ` Mike Snitzer
2010-10-10 16:41 ` Milan Broz
2010-10-10 17:07 ` Mike Snitzer
2010-10-10 18:56 ` [PATCH] Fix double free and use generic private pointer in per-cpu struct Milan Broz
2010-10-14 19:26 ` [dm-devel] " Milan Broz
2010-10-20 14:20 ` [dm-devel] [PATCH] DM-CRYPT: Scale to multiple CPUs v3 Milan Broz
2010-10-20 17:32 ` Alasdair G Kergon
2010-10-10 17:01 ` Alasdair G Kergon
2010-10-10 17:44 ` Andi Kleen
2010-10-10 18:17 ` [dm-devel] " Alasdair G Kergon
2010-10-10 18:48 ` Alasdair G Kergon
2010-10-10 18:51 ` [dm-devel] " Andi Kleen
2010-10-10 19:07 ` Alasdair G Kergon [this message]
2010-10-10 19:16 ` Andi Kleen
2010-10-10 19:31 ` Milan Broz
2010-10-10 20:20 ` Andi Kleen
2010-10-11 9:32 ` Milan Broz
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