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Date: Tue, 30 Oct 2012 10:14:40 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>,
        linux-kernel@vger.kernel.org, Andrew Vagin <avagin@openvz.org>,
        Borislav Petkov <bp@amd64.org>, David Howells <dhowells@redhat.com>,
        Frederic Weisbecker <fweisbec@gmail.com>, Jiri Olsa <jolsa@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>, Paul Mackerras <paulus@samba.org>,
        Stephane Eranian <eranian@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [GIT PULL 0/9] perf/core improvements and fixes
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* Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> On Tue, 2012-10-30 at 09:18 +0100, Ingo Molnar wrote:
> > > > The optimal way, I guess, would be to have some cache file 
> > > > with the results of such feature tests, that would be created 
> > > > and then used till the build fails using its findings, which 
> > > > would trigger a new feature check round, followed by an 
> > > > automatic rebuild. 

I did not write that.

I think making the feature tests parallel would be enough to 
speed it all up - caching brings in a new set of problems. The 
tests are mostly independent and the feature test makefile rules 
could be parallelized like the object file rules.

> autoconf!! ;-)
> 
> /me runs

hey, we build perf much faster than autoconf's 'configure' 
script finishes running ;-)

Thanks,

	Ingo