Gold timings

Michal Nowak mnowak at redhat.com
Mon Mar 15 13:40:36 UTC 2010


----- "Michal Nowak" <mnowak at redhat.com> wrote:

> ----- "Ian Lance Taylor" <iant at google.com> wrote:
> 
> > Hi, Tom Tromey pointed me at your message
> >
> http://lists.fedoraproject.org/pipermail/devel/2010-March/133039.html
> 
> Hi Ian.
> 
> > I was curious what you are timing when you compare ld and gold.  Is
> > that the total time that it takes to build the package, or just the
> > time that the linker runs?
> 
> You may be familiar with Mock which builds source RPMs in chroot. Mock
> 
> prepares build root (e.g. fedora-12-x86_64), installs BuildRequires,
> and builds given SRPM. Such a build should be repeatable. What is
> done
> is that run of this `mock' process is timed -- bad thing obviously
> here
> is that the build time includes part which is not related to build
> itself
> (i.e. build root preparation, package installation), however good is
> that
> the unrelated time is pretty much constant among runs.
> 
> If anyone knows hot to measure just the build time, I'd be glad to
> know.
> 
> > As you mention, xulrunner and thunderbird are much slower, which is
> > rather odd and completely contrary to my own testing.  Do you know
> if
> > those builds use linker scripts?  Do you have the build logs?
> 
> Unfortunately logs are gone with my yesterday's reinstall. However I
> am
> building xulrunner and thunderbird right now on different box. Will
> let
> you know till Monday.
> 
> No idea about the linking script since logs are gone.
> 
> > Also, what sort of machine were you running this on, and how much
> RAM
> > did it have?
> 
> Dualcore, Intel(R) Xeon(R) CPU 5110 @ 1.60GHz, 2GB RAM, 4GB swap.
> 

Ian -

> > I'd certainly like to get to the bottom of any cases where gold is
> > significantly slower than GNU ld.
> > 
> > I'm not on the devel at lists.fedoraproject.org mailing list.


Run with gold was run first, build root was cleared afterwards and
run with ld was run then. gold seems to be way slower.

GNU GOLD
========

[ PACKAGES xulrunner thunderbird REBUILD ]
ld:	CVS snapshot from date: 20100312
gcc:	gcc-4.4.3-4.fc12 (likely, just a guess)
kernel: Linux <BLANK> 2.6.32.9-70.fc12.x86_64 #1 SMP Wed Mar 3 04:40:41 UTC 2010 x86_64 x86_64 x86_64 GNU/Linux (from this machine)

[1/2]
Package:   xulrunner-1.9.1.8-1.fc12
Time:      18:27.26
Size:      67M
Status:    PASS

[2/2]
Package:   thunderbird-3.0.3-1.fc12
Time:      15:55.48
Size:      89M
Status:    PASS

==============================================
TOTAL: 2 PASS: 2 FAIL: 0


GNU ld
======

[ PACKAGES xulrunner thunderbird REBUILD ]
ld:	binutils-2.19.51.0.14-37.fc12 (likely, just a guess)
gcc:	gcc-4.4.3-4.fc12 (likely, just a guess)
kernel: Linux <BLANK> 2.6.32.9-70.fc12.x86_64 #1 SMP Wed Mar 3 04:40:41 UTC 2010 x86_64 x86_64 x86_64 GNU/Linux (from this machine)

[1/2]
Package:   xulrunner-1.9.1.8-1.fc12
Time:      10:00.12
Size:      66M
Status:    PASS

[2/2]
Package:   thunderbird-3.0.3-1.fc12
Time:      9:37.08
Size:      87M
Status:    PASS

==============================================
TOTAL: 2 PASS: 2 FAIL: 0



Here are the logs: http://people.redhat.com/psklenar/pub/

Michal


More information about the devel mailing list