Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
GCC timing changes after switching from13.0 profile to 17.0
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Gentoo Chat
View previous topic :: View next topic  
Author Message
Tony0945
Watchman
Watchman


Joined: 25 Jul 2006
Posts: 5127
Location: Illinois, USA

PostPosted: Thu Dec 21, 2017 3:32 am    Post subject: GCC timing changes after switching from13.0 profile to 17.0 Reply with quote

About a week ago I transitioned a desktop system from 13.0 to 17.0
I had promised to do before and after gcc timings and post the results.
The system was up to date and running gcc 6.4.0 for some time. All software had been rebuilt with gcc 6.4.0 when moving from gcc 6.3.0 to gcc 6.4.0 therefore emerge -e world was not run as part of this update. The update was accomplished by
Code:
eselect profile {number of 17.0/Desktop}
. /etc/profile
emerge -1v gcc
emerge -1v sys-devel/libtool
emerge -1v binutils
emerge -1v glibc
emerge -1a /lib*/**.a /usr/lib*/**.a
emerge -auvND world

Tests were run before and after switching to 17.0
All 13.0 tests were run with gcc-6.4.0 -pie.
All 17.0 tests were run with gcc-6.4.0 +pie
All tests were run with the following services stopped: xdm, samba, minidlna, dbus. Openssh was running but no one was logged in.
Times were taken with genlop -t. These times were 5 to ten seconds slower than those measured by “time”. Each package was emerged with “time emerge -1 <packagename> --nodeps”.
--nodeps was used to avoid measuring time for portage to examine the dependency tree. all deps were known to be satisfied.
Code:
Package         13.0 compile time 17.0 compile time.     extra for 17.0

gcc                1h  3m  9s      1h  2m 30s          -39 seconds        1.04% faster
firefox               42m 39s          42m 42s            3 seconds        0.12% slower
wxGTK                  7m 59s           7m 59s            0 seconds        no change
abiword                9m 47s          10m 12s           25 seconds        4.26% slower
mate-control-center    1m 39s           1m 39s            0 seconds        no change


System specs : Athlon X3 4G RAM 10,000 RPM hard drive. 1G swap partition plus 12G swapfile running Mate 1.12 (stopped for test) and OpenRC with eudev.
Back to top
View user's profile Send private message
Ant P.
Watchman
Watchman


Joined: 18 Apr 2009
Posts: 6920

PostPosted: Thu Dec 21, 2017 6:25 am    Post subject: Reply with quote

Thanks; good to know there's no serious regressions. Maybe there's slight performance differences at runtime, but that takes a lot more effort to measure. Though I'll say I haven't had any visible slowdown since the switch.
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Gentoo Chat All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum