From: Peter Zijlstra <peterz@infradead.org>
To: Jirka Hladky <jhladky@redhat.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
Kamil Kolakowski <kkolakow@redhat.com>
Subject: Re: Kernel 4.7rc3 - Performance drop 30-40% for SPECjbb2005 and SPECjvm2008 benchmarks against 4.6 kernel
Date: Thu, 23 Jun 2016 20:33:18 +0200 [thread overview]
Message-ID: <20160623183318.GN30154@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <CAE4VaGCYvAbvNRD65SPfLPGVCspRfUYDAtfPt-VmkukPbt-L4Q@mail.gmail.com>
On Fri, Jun 17, 2016 at 01:04:23AM +0200, Jirka Hladky wrote:
> > What kind of config and userspace setup? Do you run this cruft in a
> > cgroup of sorts?
>
> No, we don't do any special setup except to control the number of threads.
OK, so I'm fairly certain you _do_ run in a cgroup, because its made
almost impossible not to these days.
Run:
grep java /proc/sched_debug
while the thing is running. That'll show you the actual cgroup the stuff
is running in.
This modern Linux stuff stinks loads. And even Debian seems infected to
the point of almost being useless :-(
The _only_ reason I could reproduce was because I recently did an
upgrade of Debian Testing and I hadn't noticed just how messed up things
had become.
When I run it in the root cgroup (I had to kill cgmanager and reboot)
the numbers are just fine.
In any case, now I gotta go look at the cgroup code...
next prev parent reply other threads:[~2016-06-23 18:33 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-16 16:38 Kernel 4.7rc3 - Performance drop 30-40% for SPECjbb2005 and SPECjvm2008 benchmarks against 4.6 kernel Jirka Hladky
2016-06-16 17:22 ` Peter Zijlstra
2016-06-16 23:04 ` Jirka Hladky
2016-06-21 13:17 ` Jirka Hladky
2016-06-22 7:16 ` Peter Zijlstra
2016-06-22 7:49 ` Peter Zijlstra
2016-06-22 7:54 ` Peter Zijlstra
2016-06-22 9:52 ` Jirka Hladky
2016-06-22 11:12 ` Peter Zijlstra
2016-06-22 12:37 ` Jirka Hladky
2016-06-22 12:46 ` Jirka Hladky
2016-06-22 14:41 ` Jirka Hladky
2016-06-22 20:59 ` Peter Zijlstra
2016-06-22 8:20 ` Jirka Hladky
2016-06-23 18:33 ` Peter Zijlstra [this message]
2016-06-23 18:43 ` Peter Zijlstra
2016-06-24 7:44 ` Jirka Hladky
2016-06-24 8:08 ` Peter Zijlstra
2016-06-24 8:20 ` Jirka Hladky
2016-06-24 12:02 ` Peter Zijlstra
2016-06-24 12:09 ` Jirka Hladky
2016-06-24 12:30 ` Peter Zijlstra
2016-06-24 12:35 ` Jirka Hladky
2016-06-24 12:44 ` Vincent Guittot
2016-06-24 13:08 ` Jirka Hladky
2016-06-24 13:09 ` Peter Zijlstra
2016-06-24 13:23 ` Vincent Guittot
2016-06-24 13:33 ` Peter Zijlstra
2016-06-24 13:45 ` Peter Zijlstra
2016-06-24 13:42 ` Peter Zijlstra
2016-06-24 15:54 ` Peter Zijlstra
2016-06-24 22:13 ` Jirka Hladky
-- strict thread matches above, loose matches on Subject: below --
2016-06-22 7:37 Branimir Maksimovic
2016-06-22 8:25 ` Jirka Hladky
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=20160623183318.GN30154@twins.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=jhladky@redhat.com \
--cc=kkolakow@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.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.