From: Markus Trippelsdorf <markus@trippelsdorf.de>
To: Richard Guenther <richard.guenther@gmail.com>
Cc: Eric Botcazou <ebotcazou@adacore.com>,
gcc-patches@gcc.gnu.org, Ian Lance Taylor <iant@google.com>,
Diego Novillo <dnovillo@google.com>,
gcc@gcc.gnu.org
Subject: Re: PATCH RFA: Build stages 2 and 3 with C++
Date: Sun, 17 Jul 2011 22:37:00 -0000 [thread overview]
Message-ID: <20110717175514.GB14418@x4.trippels.de> (raw)
In-Reply-To: <20110717165451.GA14418@x4.trippels.de>
On 2011.07.17 at 18:54 +0200, Markus Trippelsdorf wrote:
> On 2011.07.17 at 18:30 +0200, Richard Guenther wrote:
> > On Sun, Jul 17, 2011 at 1:30 PM, Eric Botcazou <ebotcazou@adacore.com> wrote:
> > >> I have measured it at some point and IIRC it was about 10% slower
> > >> (comparing C bootstrap with C++ in stag1 languages with C++ bootstrap,
> > >> not sure if that included bootstrapping libstdc++ for the former).
> > >
> > > IMO acceptable now that the build time of libjava has been halved.
> >
> > Actually the penalty for using C++ was only 1.5%, that of bootstrapping C++ and
> > libstdc++ was 15%. For reference:
>
> I've tested the difference today on an average 4 CPU machine with 8GB
> RAM. This is the result of otherwise identical LTO+PGO builds:
>
> --enable-build-with-cxx make -j4 profiledbootstrap 3384.20s user 177.02s system 291% cpu 20:23.12 total
> <default> make -j4 profiledbootstrap 3011.03s user 144.30s system 297% cpu 17:41.59 total
>
> That's a ~15% increase in build time.
And I guess that most of it comes from building libstdc++ to train the
instrumented compiler. This doesn't happen in the default case AFAICS.
--
Markus
next prev parent reply other threads:[~2011-07-17 17:55 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-16 6:56 Ian Lance Taylor
2011-07-16 7:05 ` Andrew Pinski
2011-07-16 7:48 ` Ian Lance Taylor
2011-07-16 7:59 ` Basile Starynkevitch
2011-07-17 3:17 ` Ian Lance Taylor
2011-07-16 16:11 ` Diego Novillo
2011-07-16 22:58 ` Ian Lance Taylor
2011-07-17 10:36 ` Richard Guenther
2011-07-17 12:21 ` Eric Botcazou
2011-07-17 16:55 ` Richard Guenther
2011-07-17 17:55 ` Markus Trippelsdorf
2011-07-17 22:37 ` Markus Trippelsdorf [this message]
2011-09-04 17:20 ` Thomas Schwinge
2011-07-16 20:40 ` Toon Moene
2011-07-19 21:33 ` Ian Lance Taylor
2011-07-19 22:24 ` Gabriel Dos Reis
2011-07-20 0:46 ` H.J. Lu
2011-07-20 1:15 ` H.J. Lu
2011-07-20 6:28 ` David Edelsohn
2011-07-20 9:34 ` Jonathan Wakely
2011-07-20 11:02 ` Jonathan Wakely
2011-07-20 12:41 ` David Edelsohn
2011-07-20 12:48 ` Richard Guenther
2011-07-20 14:07 ` Diego Novillo
2011-07-20 14:34 ` Ian Lance Taylor
2011-07-20 15:35 ` Jonathan Wakely
2011-07-20 15:06 ` Toon Moene
2011-07-20 15:23 ` Ian Lance Taylor
2011-07-20 15:53 ` David Edelsohn
2011-07-20 15:55 ` Ian Lance Taylor
2011-07-20 20:05 ` David Edelsohn
2011-07-20 20:53 ` Ian Lance Taylor
2011-07-20 21:06 ` Mike Stump
2011-07-21 0:10 ` Ian Lance Taylor
2011-07-21 9:40 ` Basile Starynkevitch
2011-07-21 16:06 ` Ian Lance Taylor
2011-07-21 17:44 ` Jakub Jelinek
2011-07-21 19:40 ` Ian Lance Taylor
2011-07-21 20:12 ` Basile Starynkevitch
2011-07-21 22:38 ` Ian Lance Taylor
2011-07-21 6:57 ` David Edelsohn
2011-07-21 7:25 ` Eric Botcazou
2011-07-21 14:24 ` David Edelsohn
2011-07-20 17:58 ` Thomas Schwinge
2011-07-20 21:41 ` Toon Moene
2011-07-31 23:20 ` Marc Glisse
2011-08-01 9:14 ` Richard Guenther
2011-08-01 9:53 ` Joseph S. Myers
2011-08-01 9:59 ` Richard Guenther
2011-08-01 10:05 ` Marc Glisse
2011-08-08 17:42 ` Romain Geissler
2011-08-08 18:49 ` Ian Lance Taylor
2011-08-08 19:40 ` Romain Geissler
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