linux-kernel - Re: [GIT PULL] perf fixes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 24 Jan 2011 22:25:26 +0100
From:	Ingo Molnar <mingo@...e.hu>
To:	Arnaldo Carvalho de Melo <acme@...hat.com>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	linux-kernel@...r.kernel.org,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Frédéric Weisbecker <fweisbec@...il.com>,
	Steven Rostedt <rostedt@...dmis.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [GIT PULL] perf fixes


* Arnaldo Carvalho de Melo <acme@...hat.com> wrote:

> Em Tue, Jan 25, 2011 at 06:27:31AM +1000, Linus Torvalds escreveu:
> > On Tue, Jan 25, 2011 at 6:17 AM, Linus Torvalds
> > <torvalds@...ux-foundation.org> wrote:
> > >
> > > It only happens for me with "g". With "perf record -af sleep 10" it worked.
> > 
> > Actually, it's something subtler than that. It must depend on the
> > actual data, because now when I tried it again, it worked with 'g'
> > too. I hadn't saved the old perf.data that caused the lockup (it got
> > overwritten by the non-g test), and now when I try to re-create it it
> > doesn't hang on the result.
> > 
> > So it's probably some very specific data pattern that causes it.
> > 
> > (And I don't know if it's a hard hang - it could just be something
> > _very_ slow. But we're talking half a minute kind of slow).
> 
> Was this on a freshly installed machine? Or on a freshly updated one?
> 
> Probably its the build-id collecting at the end of a session, on the
> first run you had a cold cache and it had to figure out which binaries
> to cache on ~/.debug, second time it was already cached so it was fast.

Hm, it would be nice to not surprise users with an unlimited-timeout, up to half a 
minute 'frozen' app. Can we possibly display a more finegrained progress indicator?

Thanks,

	Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/