# git-annotate efficiency 4 messages from 2006-02-24 to 2006-02-24. Participants: Morten Welinder, Randal L. Schwartz, Ryan Anderson. Thread: https://gitlist.dev/t/3455 ## Morten Welinder, 2006-02-24 15:37 Subject: git-annotate efficiency Message-ID: <118833cc0602240737i42acdc90sb8f93dde1a1bc035@mail.gmail.com> URL: https://gitlist.dev/e/118833cc0602240737i42acdc90sb8f93dde1a1bc035%40mail.gmail.com ``` So I wanted to give git-annotate a spin and typed... git annotate Makefile Bad idea. It's been ten minutes and no output yet. While the script only appears to use ~20% of cpu according to top, an strace shows that it spins off a huge number of very short-lived subprocesses. Morten ... rt_sigaction(SIGQUIT, {SIG_IGN}, {SIG_DFL}, 8) = 0 waitpid(1539, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0) = 1539 --- SIGCHLD (Child exited) @ 0 (0) --- rt_sigaction(SIGHUP, {SIG_DFL}, NULL, 8) = 0 rt_sigaction(SIGINT, {SIG_DFL}, NULL, 8) = 0 rt_sigaction(SIGQUIT, {SIG_DFL}, NULL, 8) = 0 pipe([3, 4]) = 0 pipe([5, 6]) = 0 clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x401db708) = 1540 close(6) = 0 close(4) = 0 read(5, "", 4) = 0 close(5) = 0 ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0xbfffc718) = -1 EINVAL (Invalid argument) _llseek(3, 0, 0xbfffc760, SEEK_CUR) = -1 ESPIPE (Illegal seek) fcntl64(3, F_SETFD, FD_CLOEXEC) = 0 read(3, "diff --git a/Makefile b/Makefile"..., 4096) = 63 read(3, "--- a/Makefile\n+++ b/Makefile\n@@"..., 4096) = 203 --- SIGCHLD (Child exited) @ 0 (0) --- read(3, "", 4096) = 0 close(3) = 0 rt_sigaction(SIGHUP, {SIG_IGN}, {SIG_DFL}, 8) = 0 rt_sigaction(SIGINT, {SIG_IGN}, {SIG_DFL}, 8) = 0 ... ``` ## Morten Welinder, 2006-02-24 18:00 Subject: Re: git-annotate efficiency Message-ID: <118833cc0602241000p4e4c8017u3e3afe76fbbd75a4@mail.gmail.com> URL: https://gitlist.dev/e/118833cc0602241000p4e4c8017u3e3afe76fbbd75a4%40mail.gmail.com In-Reply-To: <118833cc0602240737i42acdc90sb8f93dde1a1bc035@mail.gmail.com> ``` It looks like handle_rev is seeing the same revisions over and over again. I don't know why that would be, but the following patch just skips dups. I have no idea if it is right, though. Morten diff --git a/git-annotate.perl b/git-annotate.perl index 3800c46..a5e2d86 100755 --- a/git-annotate.perl +++ b/git-annotate.perl @@ -117,7 +117,10 @@ sub init_claim { sub handle_rev { my $i = 0; + my %seen = (); while (my $rev = shift @revqueue) { + next if $seen{$rev}; + $seen{$rev} = 1; my %revinfo = git_commit_info($rev); ``` ## Randal L. Schwartz, 2006-02-24 19:06 Subject: Re: git-annotate efficiency Message-ID: <86oe0wbmqn.fsf@blue.stonehenge.com> URL: https://gitlist.dev/e/86oe0wbmqn.fsf%40blue.stonehenge.com In-Reply-To: <118833cc0602241000p4e4c8017u3e3afe76fbbd75a4@mail.gmail.com> ``` >>>>> "Morten" == Morten Welinder writes: Morten> It looks like handle_rev is seeing the same revisions over and over again. Morten> I don't know why that would be, but the following patch just skips dups. Morten> I have no idea if it is right, though. Morten> Morten Morten> diff --git a/git-annotate.perl b/git-annotate.perl Morten> index 3800c46..a5e2d86 100755 Morten> --- a/git-annotate.perl Morten> +++ b/git-annotate.perl Morten> @@ -117,7 +117,10 @@ sub init_claim { Morten> sub handle_rev { Morten> my $i = 0; Morten> + my %seen = (); Morten> while (my $rev = shift @revqueue) { Morten> + next if $seen{$rev}; Morten> + $seen{$rev} = 1; Morten> my %revinfo = git_commit_info($rev); The traditional idiom for that is next if $seen{$rev}++; -- Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095 Perl/Unix/security consulting, Technical writing, Comedy, etc. etc. See PerlTraining.Stonehenge.com for onsite and open-enrollment Perl training! ``` ## Ryan Anderson, 2006-02-24 19:42 Subject: Re: git-annotate efficiency Message-ID: <20060224194231.GA18691@mythryan2.michonline.com> URL: https://gitlist.dev/e/20060224194231.GA18691%40mythryan2.michonline.com In-Reply-To: <118833cc0602241000p4e4c8017u3e3afe76fbbd75a4@mail.gmail.com> ``` On Fri, Feb 24, 2006 at 01:00:24PM -0500, Morten Welinder wrote: > It looks like handle_rev is seeing the same revisions over and over again. > I don't know why that would be, but the following patch just skips dups. > I have no idea if it is right, though. Merges. a--b--c--d--f \-g--h--/ It would do f,d,c,b,a + f,h,g,b,a So yes, this fix is correct, and Junio, I'll be doing some changes this weekend and send it along with a few other things. (On a medium-sized test tree at work with 3500 commits in the tree, 37 on the main Makefile (6 merges), this cuts the annotate time from 10s to a little over 2, so it's, umm, very worthwhile.) > > Morten > > > diff --git a/git-annotate.perl b/git-annotate.perl > index 3800c46..a5e2d86 100755 > --- a/git-annotate.perl > +++ b/git-annotate.perl > @@ -117,7 +117,10 @@ sub init_claim { > > sub handle_rev { > my $i = 0; > + my %seen = (); > while (my $rev = shift @revqueue) { > + next if $seen{$rev}; > + $seen{$rev} = 1; > > my %revinfo = git_commit_info($rev); > - > To unsubscribe from this list: send the line "unsubscribe git" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Ryan Anderson sometimes Pug Majere ```