From: David Ahern <david.ahern@oracle.com>
To: Don Zickus <dzickus@redhat.com>
Cc: acme@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] perf tools: Fix ppid for non-main thread
Date: Thu, 09 Apr 2015 11:08:09 -0600 [thread overview]
Message-ID: <5526B1F9.3020002@oracle.com> (raw)
In-Reply-To: <20150409170519.GK175361@redhat.com>
On 4/9/15 11:05 AM, Don Zickus wrote:
> On Thu, Apr 09, 2015 at 12:48:27PM -0400, David Ahern wrote:
>> >Commit ca6c41c59b9 sets the ppid based on what is read from the
>> >/proc/pid/status file when synthesizing fork events. This is correct
>> >thing to do for new processes but not threads of a process. Fix
>> >ppid for threads to be the main thread when synthesizing fork events
>> >(ie., assume main thread spawned all sub-threads in a process).
> That sounds right.:-) Sorry I should have noticed that a couple of weeks
> ago.
>
> Acked-by: Don Zickus<dzickus@redhat.com>
>
I believe this explains the performance delta you noticed with
specjbb/jvm. Arnaldo is the one that figured out the performance hit is
from cloning maps; from that analysis I realized what the goof was.
David
next prev parent reply other threads:[~2015-04-09 17:08 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-09 16:48 [PATCH] perf tools: Fix ppid for non-main thread David Ahern
2015-04-09 17:05 ` Don Zickus
2015-04-09 17:08 ` David Ahern [this message]
2015-04-11 6:36 ` [tip:perf/core] perf tools: Fix synthesizing fork_event.ppid " tip-bot for David Ahern
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=5526B1F9.3020002@oracle.com \
--to=david.ahern@oracle.com \
--cc=acme@kernel.org \
--cc=dzickus@redhat.com \
--cc=linux-kernel@vger.kernel.org \
/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.