All of lore.kernel.org
 help / color / mirror / Atom feed
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

  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

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=50CB84A1.1060205@eu.citrix.com \
    --to=george.dunlap@eu.citrix.com \
    --cc=Ian.Campbell@citrix.com \
    --cc=dario.faggioli@citrix.com \
    --cc=keir@xen.org \
    --cc=xen-devel@lists.xensource.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.