Date: Wed, 18 Sep 2013 15:35:25 +0200
From: Ingo Molnar <mingo@kernel.org>
To: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Tom Zanussi <tzanussi@gmail.com>, Steven Rostedt <srostedt@redhat.com>,
        Ingo Molnar <mingo@elte.hu>, Jiri Olsa <jolsa@redhat.com>,
        Masami Hiramatsu <mhiramat@redhat.com>,
        Oleg Nesterov <oleg@redhat.com>, linux-kernel@vger.kernel.org,
        Denys Vlasenko <vda.linux@googlemail.com>
Subject: Re: [RFC] Full syscall argument decode in "perf trace"
Message-ID: <20130918133525.GB8141@gmail.com>
References: <20130917190606.GB3918@infradead.org>
 <52398FF1.5020502@redhat.com>
 <5239A0BE.7050203@gmail.com>
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* David Ahern <dsahern@gmail.com> wrote:

> On 9/18/13 5:35 AM, Denys Vlasenko wrote:
> >Therefore my question should be restated as:
> >
> >Would perf developers accept the "syscall pausing" feature,
> >or it won't be accepted?
> 
> I have been using perf-trace a lot lately specifically because it is 
> effectively a 'passive' observer of the task (e.g., time-sensitive tasks 
> can be traced with perf but not with strace).

Yes, this is not just an important but a primary design goal for all perf 
utilities: if the tracing buffers used are large enough then it should be 
a nearly zero-overhead observer that preserves all previous patterns of 
behavior as much as possible.

Thanks,

	Ingo
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