# git-merge performance 3 messages from 2007-10-16 to 2007-10-16. Participants: Andrew Morton, Andreas Ericsson. Thread: https://gitlist.dev/t/10320 ## Andrew Morton, 2007-10-16 17:17 Subject: git-merge performance Message-ID: <20071016101748.ff132685.akpm@linux-foundation.org> URL: https://gitlist.dev/e/20071016101748.ff132685.akpm%40linux-foundation.org ``` My git-pulling script (git-1.4.2) seems to have got quite a bit slower since the post-2.6.23 patchflood. I just did a bit of poking and it's git-merge which is taking most of the time. Using git-watchdog as an example: box:/usr/src/git26> cat .git/branches/git-watchdog git+ssh://master.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog-mm.git box:/usr/src/git26> git reset --hard origin box:/usr/src/git26> git fetch git-watchdog box:/usr/src/git26> time git merge --no-commit 'test merge' HEAD FETCH_HEAD > /dev/null Automatic merge failed; fix conflicts and then commit the result. git merge --no-commit 'test merge' HEAD FETCH_HEAD > /dev/null 47.03s user 26.53s system 97% cpu 1:15.67 total Try git-md-accel: box:/usr/src/git26> cat .git/branches/git-md-accel git://lost.foo-projects.org/~dwillia2/git/iop#md-for-linus box:/usr/src/git26> time git reset --hard origin git reset --hard origin 0.51s user 0.11s system 100% cpu 0.615 total box:/usr/src/git26> time git fetch git-md-accel git fetch git-md-accel 0.12s user 0.05s system 11% cpu 1.379 total box:/usr/src/git26> time git merge --no-commit 'test merge' HEAD FETCH_HEAD > /dev/null Automatic merge failed; fix conflicts and then commit the result. git merge --no-commit 'test merge' HEAD FETCH_HEAD > /dev/null 42.52s user 24.18s system 96% cpu 1:08.93 total And git-unionfs: box:/usr/src/git26> cat .git/branches/git-unionfs git+ssh://master.kernel.org/pub/scm/linux/kernel/git/ezk/unionfs.git box:/usr/src/git26> time git reset --hard origin git reset --hard origin 0.52s user 0.09s system 100% cpu 0.611 total box:/usr/src/git26> time git fetch git-unionfs git fetch git-unionfs 0.16s user 0.03s system 8% cpu 2.285 total box:/usr/src/git26> time git merge --no-commit 'test merge' HEAD FETCH_HEAD > /dev/null Automatic merge went well; stopped before committing as requested git merge --no-commit 'test merge' HEAD FETCH_HEAD > /dev/null 42.81s user 24.86s system 96% cpu 1:09.98 total Everything is in pagecache, and I just did git-repack -a -d;git prune;git-fsck-objects --full. Pulling 70-80 trees at a minute and a half each gets a bit dull ;) ``` ## Andreas Ericsson, 2007-10-16 17:34 Subject: Re: git-merge performance Message-ID: <4714F612.2010905@op5.se> URL: https://gitlist.dev/e/4714F612.2010905%40op5.se In-Reply-To: <20071016101748.ff132685.akpm@linux-foundation.org> ``` Andrew Morton wrote: > My git-pulling script (git-1.4.2) seems to have got quite a bit slower > since the post-2.6.23 patchflood. I just did a bit of poking and it's > git-merge which is taking most of the time. > That's odd. If it had been the remote fetching it would have been understandable. Is this also happening with more recent gits? I know there are some significant performance-improvements in 1.5.3.4 (or below). -- Andreas Ericsson andreas.ericsson@op5.se OP5 AB www.op5.se Tel: +46 8-230225 Fax: +46 8-230231 ``` ## Andrew Morton, 2007-10-16 18:18 Subject: Re: git-merge performance Message-ID: <20071016111825.5a142f00.akpm@linux-foundation.org> URL: https://gitlist.dev/e/20071016111825.5a142f00.akpm%40linux-foundation.org In-Reply-To: <4714F612.2010905@op5.se> ``` On Tue, 16 Oct 2007 19:34:10 +0200 Andreas Ericsson wrote: > Andrew Morton wrote: > > My git-pulling script (git-1.4.2) seems to have got quite a bit slower > > since the post-2.6.23 patchflood. I just did a bit of poking and it's > > git-merge which is taking most of the time. > > > > That's odd. If it had been the remote fetching it would have been > understandable. Is this also happening with more recent gits? I know there > are some significant performance-improvements in 1.5.3.4 (or below). > 1.5.0 is no faster, but 1.5.3 appears to be seven times quicker. Neato. ```