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#!/usr/bin/perl
use strict;
use warnings;
use File::Copy;
use File::Spec;
use File::Path qw(remove_tree make_path);
use File::Find;
use File::Basename;
use Cwd qw(getcwd abs_path);
use Time::HiRes qw(time);
my ($files, $depth, $total_commits, $file_perc, $change_perc) = @ARGV;
if (!defined $files || !defined $depth || !defined $total_commits || !defined $file_perc || !defined $change_perc) {
die "Usage: perl bm_rebase.pl <file_count> <depth> <total_commits> <file_perc> <change_perc>\n";
}
my $base_dir = getcwd();
my $urn_bin = abs_path(File::Spec->catfile("..", "urn"));
my $seed_bin = abs_path("seed.pl");
my $bm_repo = "sandbox";
my $sample_rate = int($total_commits / 5) || 1;
my %results;
my $initial_repo_size = "0 KB";
my $rebase_count = 0;
my %last_base_hashes;
my $global_tick = 0;
sub get_size {
my $dir = shift;
return "0 KB" unless -d $dir;
my $size = `du -sk $dir 2>/dev/null`;
$size =~ /^(\d+)/;
return ($1 || 0) . " KB";
}
sub count_inodes {
my $dir = shift;
return 0 unless -d $dir;
my $count = `find $dir 2>/dev/null | wc -l`;
$count =~ s/\s+//g;
return $count || 0;
}
sub track_rebases {
return unless -f ".urn/index";
open(my $fh, '<', ".urn/index") or return;
while (<$fh>) {
chomp;
my @cols = split(/\t/);
next unless @cols >= 6;
my ($b_hash, $path) = ($cols[2], $cols[5]);
if (exists $last_base_hashes{$path} && $last_base_hashes{$path} ne $b_hash) {
$rebase_count++;
}
$last_base_hashes{$path} = $b_hash;
}
close($fh);
}
sub run_rebase_benchmark {
my ($tool_name) = @_;
print ">>> Starting REBASE BENCHMARK: $tool_name\n";
remove_tree($bm_repo) if -d $bm_repo;
system("perl $seed_bin $files $depth > /dev/null 2>&1");
if ($initial_repo_size eq "0 KB") { $initial_repo_size = get_size($bm_repo); }
chdir($bm_repo) or die $!;
my $init_cmd = ($tool_name eq "URN") ? "perl $urn_bin init" : "git init";
my $add_cmd = ($tool_name eq "URN") ? "perl $urn_bin add ." : "git add .";
system("$init_cmd > /dev/null 2>&1");
system("$add_cmd > /dev/null 2>&1");
system(($tool_name eq "URN" ? "perl $urn_bin" : "git") . " commit -m 'initial' > /dev/null 2>&1");
track_rebases() if $tool_name eq "URN";
my @file_list;
find(sub { push @file_list, $File::Find::name if -f $_ && $File::Find::name !~ /\.(git|urn)/ }, ".");
my $num_to_change = int(scalar(@file_list) * ($file_perc / 100)) || 1;
my @target_files = @file_list[0 .. $num_to_change - 1];
for my $i (2 .. $total_commits) {
my $debug_dir = "/tmp/urn/commit_$i";
make_path($debug_dir) unless -d $debug_dir;
for my $target (@target_files) {
open(my $fh, '<:raw', $target) or die "Read fail: $target - $!";
my $content = do { local $/; <$fh> };
close($fh);
$global_tick++;
my $ts = time();
my $header = "C$i-T$ts-N$global_tick ";
my $total_bytes = length($content);
my $min_len = length($header);
my $to_change = int($total_bytes * ($change_perc / 100));
$to_change = $min_len if $to_change < $min_len;
$to_change = $total_bytes if $to_change > $total_bytes;
my $new_segment = substr($header . ("." x $to_change), 0, $to_change);
substr($content, 0, $to_change, $new_segment);
open(my $out, '>:raw', $target) or die "Write fail: $target - $!";
print $out $content;
close($out);
my $target_name = basename($target);
copy($target, "$debug_dir/$target_name") or warn "Backup failed: $!";
utime(undef, undef, $target);
}
my $cmd = ($tool_name eq "URN")
? "perl $urn_bin add . && perl $urn_bin commit -m 'c$i'"
: "git add . && git commit -m 'c$i'";
if ($i % $sample_rate == 0 || $i == $total_commits) {
my $raw_output = `/usr/bin/time -l sh -c "$cmd" 2>&1`;
if ($tool_name eq "URN") {
track_rebases();
}
my ($real, $rss, $maj, $min) = (0, 0, 0, 0);
$real = $1 if $raw_output =~ /(\d+\.\d+)\s+real/;
$rss = sprintf("%.2f MB", $1 / 1024 / 1024) if $raw_output =~ /(\d+)\s+maximum resident set size/;
$min = $1 if $raw_output =~ /(\d+)\s+page reclaims/;
$maj = $1 if $raw_output =~ /(\d+)\s+page faults/;
my $meta = ($tool_name eq "URN") ? ".urn" : ".git";
$results{$i}{$tool_name} = {
real => $real . "s",
rss => $rss,
faults => "Maj:$maj / Min:$min",
inodes => count_inodes($meta),
size => get_size($meta),
};
print " [Commit $i] $tool_name sampled.\n";
} else {
system("$cmd > /dev/null 2>&1");
track_rebases() if $tool_name eq "URN";
}
}
chdir($base_dir);
}
$rebase_count = 0;
%last_base_hashes = ();
run_rebase_benchmark("URN");
run_rebase_benchmark("GIT");
my $out_file = "BM_REBASE_${files}_${total_commits}.txt";
open(my $res, '>', $out_file) or die $!;
print $res "=============================================================\n";
print $res " REBASE BENCHMARK: $files files ($total_commits commits)\n";
print $res " CONDITIONS: Depth=$depth, Files Mod=$file_perc%, Change=$change_perc%\n";
print $res "=============================================================\n\n";
foreach my $i (sort { $a <=> $b } keys %results) {
my $u = $results{$i}{"URN"};
my $g = $results{$i}{"GIT"};
print $res "SNAPSHOT: Commit #$i\n";
print $res "-------------------------------------------------------------\n";
printf $res "%-15s | %-20s | %-20s\n", "METRIC", "URN", "GIT";
print $res "----------------+----------------------+---------------------\n";
printf $res "%-15s | %20s | %20s\n", "Time", $u->{real}, $g->{real};
printf $res "%-15s | %20s | %20s\n", "Max RSS", $u->{rss}, $g->{rss};
printf $res "%-15s | %20s | %20s\n", "Page faults", $u->{faults}, $g->{faults};
printf $res "%-15s | %20s | %20s\n", "Inodes", $u->{inodes}, $g->{inodes};
printf $res "%-15s | %20s | %20s\n", "Repo size", $u->{size}, $g->{size};
print $res "-------------------------------------------------------------\n\n";
}
print $res "TOTAL URN REBASES: $rebase_count\n";
close($res);
exec "less $out_file";
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