From: George Dunlap <george.dunlap@eu.citrix.com>
To: Dario Faggioli <dario.faggioli@citrix.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>,
"Keir (Xen.org)" <keir@xen.org>,
Ian Campbell <Ian.Campbell@citrix.com>
Subject: Re: [PATCH 4 of 6 v2] xen: tracing: report where a VCPU wakes up
Date: Fri, 14 Dec 2012 19:57:21 +0000 [thread overview]
Message-ID: <50CB84A1.1060205@eu.citrix.com> (raw)
In-Reply-To: <7a199dea34425e890b31.1355280774@Solace>
On 12/12/12 02:52, Dario Faggioli wrote:
> When looking at traces, it turns out to be useful to know where a
> waking-up VCPU is being queued. Yes, that is always the CPU where
> it ran last, but that information can well be lost in past trace
> records!
When you say "lost in past trace records", do you primarily mean that
the records themselves have been lost (due to the per-cpu trace buffers
filling up), or do you mean that it may be way way back and you don't
want to go back and find it?
If the latter, I think the best thing to do would be to just augment
xenalyze to keep track of that information and print it when it sees the
wake record.
-George
next prev parent reply other threads:[~2012-12-14 19:57 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-12 2:52 [PATCH 0 of 6 v2] xen: sched_credit: fix picking & tickling and also add some tracing Dario Faggioli
2012-12-12 2:52 ` [PATCH 1 of 6 v2] xen: sched_credit: improve picking up the idlal CPU for a VCPU Dario Faggioli
2012-12-12 10:04 ` Jan Beulich
2012-12-12 10:19 ` Dario Faggioli
2012-12-12 10:30 ` Jan Beulich
2012-12-12 10:38 ` Dario Faggioli
2012-12-14 19:50 ` George Dunlap
2012-12-17 8:35 ` Jan Beulich
2012-12-17 14:36 ` Dario Faggioli
2012-12-14 19:16 ` George Dunlap
2012-12-12 2:52 ` [PATCH 2 of 6 v2] xen: sched_credit: improve tickling of idle CPUs Dario Faggioli
2012-12-14 19:29 ` George Dunlap
2012-12-12 2:52 ` [PATCH 3 of 6 v2] xen: sched_credit: use current_on_cpu() when appropriate Dario Faggioli
2012-12-14 19:39 ` George Dunlap
2012-12-17 14:41 ` Dario Faggioli
2012-12-12 2:52 ` [PATCH 4 of 6 v2] xen: tracing: report where a VCPU wakes up Dario Faggioli
2012-12-14 19:57 ` George Dunlap [this message]
2012-12-17 14:43 ` Dario Faggioli
2012-12-12 2:52 ` [PATCH 5 of 6 v2] xen: tracing: introduce per-scheduler trace event IDs Dario Faggioli
2012-12-14 20:00 ` George Dunlap
2012-12-12 2:52 ` [PATCH 6 of 6 v2] xen: sched_credit: add some tracing Dario Faggioli
2012-12-14 20:05 ` George Dunlap
2012-12-17 14:45 ` Dario Faggioli
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