#!/usr/bin/perl
#
# This tool will print vaguely pretty information about a pack. It
# expects the output of "git verify-pack -v" as input on stdin.
#
# $ git verify-pack -v | packinfo.pl
#
# This prints some full-pack statistics; currently "all sizes", "all
# path sizes", "tree sizes", "tree path sizes", and "depths".
#
# * "all sizes" stats are across every object size in the file;
# full sizes for base objects, and delta size for deltas.
# * "all path sizes" stats are across all object's "path sizes".
# A path size is the sum of the size of the delta chain, including the
# base object. In other words, it's how many bytes need be read to
# reassemble the file from deltas.
# * "tree sizes" are object sizes grouped into delta trees.
# * "tree path sizes" are path sizes grouped into delta trees.
# * "depths" should be obvious.
#
# When run as:
#
# $ git verify-pack -v | packinfo.pl -tree
#
# the trees of objects are output along with the stats. This looks
# like:
#
# 0 commit 031321c6... 803 803
#
# 0 blob 03156f21... 1767 1767
# 1 blob f52a9d7f... 10 1777
# 2 blob a8cc5739... 51 1828
# 3 blob 660e90b1... 15 1843
# 4 blob 0cb8e3bb... 33 1876
# 2 blob e48607f0... 311 2088
# size: count 6 total 2187 min 10 max 1767 mean 364.50 median 51 std_dev 635.85
# path size: count 6 total 11179 min 1767 max 2088 mean 1863.17 median 1843 std_dev 107.26
#
# The first number after the sha1 is the object size, the second
# number is the path size. The statistics are across all objects in
# the previous delta tree. Obviously they are omitted for trees of
# one object.
#
# When run as:
#
# $ git verify-pack -v | packinfo.pl -tree -filenames
#
# it adds filenames to the tree. Getting this information is slow:
#
# 0 blob 03156f21... 1767 1767 Documentation/git-lost-found.txt @ tags/v1.2.0~142
# 1 blob f52a9d7f... 10 1777 Documentation/git-lost-found.txt @ tags/v1.5.0-rc1~74
# 2 blob a8cc5739... 51 1828 Documentation/git-lost+found.txt @ tags/v0.99.9h^0
# 3 blob 660e90b1... 15 1843 Documentation/git-lost+found.txt @ master~3222^2~2
# 4 blob 0cb8e3bb... 33 1876 Documentation/git-lost+found.txt @ master~3222^2~3
# 2 blob e48607f0... 311 2088 Documentation/git-lost-found.txt @ tags/v1.5.2-rc3~4
# size: count 6 total 2187 min 10 max 1767 mean 364.50 median 51 std_dev 635.85
# path size: count 6 total 11179 min 1767 max 2088 mean 1863.17 median 1843 std_dev 107.26
#
# When run as:
#
# $ git verify-pack -v | packinfo.pl -dump
#
# it prints out "sha1 size pathsize depth" for each sha1 in lexical
# order.
#
# 000079a2eaef17b7eae70e1f0f635557ea67b644 30 472 7
# 00013cafe6980411aa6fdd940784917b5ff50f0a 44 1542 4
# 000182eacf99cde27d5916aa415921924b82972c 499 499 0
# ...
#
# This is handy for comparing two packs. Adding "-filenames" will add
# filenames, as per "-tree -filenames" above.
use strict;
use Getopt::Long;
my $filenames = 0;
my $tree = 0;
my $dump = 0;
GetOptions("tree" => \$tree,
"filenames" => \$filenames,
"dump" => \$dump);
my %parents;
my %children;
my %sizes;
my @roots;
my %paths;
my %types;
my @commits;
my %names;
my %depths;
my @depths;
while (<STDIN>) {
my ($sha1, $type, $size, $space, $offset, $depth, $parent) = split(/\s+/, $_);
next unless ($sha1 =~ /^[0-9a-f]{40}$/);
$depths{$sha1} = $depth || 0;
push(@depths, $depth || 0);
push(@commits, $sha1) if ($type eq 'commit');
push(@roots, $sha1) unless $parent;
$parents{$sha1} = $parent;
$types{$sha1} = $type;
push(@{$children{$parent}}, $sha1);
$sizes{$sha1} = $size;
}
if ($filenames && ($tree || $dump)) {
open(NAMES, "git name-rev --all|");
while (<NAMES>) {
if (/^(\S+)\s+(.*)$/) {
my ($sha1, $name) = ($1, $2);
$names{$sha1} = $name;
}
}
close NAMES;
for my $commit (@commits) {
my $name = $names{$commit};
open(TREE, "git ls-tree -t -r $commit|");
print STDERR "Plumbing tree $name\n";
while (<TREE>) {
if (/^(\S+)\s+(\S+)\s+(\S+)\s+(.*)$/) {
my ($mode, $type, $sha1, $path) = ($1, $2, $3, $4);
$paths{$sha1} = "$path @ $name";
}
}
close TREE;
}
}
sub stats {
my @data = sort {$a <=> $b} @_;
my $min = $data[0];
my $max = $data[$#data];
my $total = 0;
my $count = scalar @data;
for my $datum (@data) {
$total += $datum;
}
my $mean = $total / $count;
my $median = $data[int(@data / 2)];
my $diff_sum = 0;
for my $datum (@data) {
$diff_sum += ($datum - $mean)**2;
}
my $std_dev = sqrt($diff_sum / $count);
return ($count, $total, $min, $max, $mean, $median, $std_dev);
}
sub print_stats {
my $name = shift;
my ($count, $total, $min, $max, $mean, $median, $std_dev) = stats(@_);
printf("%s: count %s total %s min %s max %s mean %.2f median %s std_dev %.2f\n",
$name, $count, $total, $min, $max, $mean, $median, $std_dev);
}
my @sizes;
my @path_sizes;
my @all_sizes;
my @all_path_sizes;
my %path_sizes;
sub dig {
my ($sha1, $depth, $path_size) = @_;
$path_size += $sizes{$sha1};
push(@sizes, $sizes{$sha1});
push(@all_sizes, $sizes{$sha1});
push(@path_sizes, $path_size);
push(@all_path_sizes, $path_size);
$path_sizes{$sha1} = $path_size;
if ($tree) {
printf("%3d%s %6s %s %8d %8d %s\n",
$depth, (" " x $depth), $types{$sha1},
$sha1, $sizes{$sha1}, $path_size, $paths{$sha1});
}
for my $child (@{$children{$sha1}}) {
dig($child, $depth + 1, $path_size);
}
}
my @tree_sizes;
my @tree_path_sizes;
for my $root (@roots) {
undef @sizes;
undef @path_sizes;
dig($root, 0, 0);
my ($aa, $sz_total) = stats(@sizes);
my ($bb, $psz_total) = stats(@path_sizes);
push(@tree_sizes, $sz_total);
push(@tree_path_sizes, $psz_total);
if ($tree) {
if (@sizes > 1) {
print_stats(" size", @sizes);
print_stats("path size", @path_sizes);
}
print "\n";
}
}
if ($dump) {
for my $sha1 (sort keys %sizes) {
print "$sha1 $sizes{$sha1} $path_sizes{$sha1} $depths{$sha1} $paths{$sha1}\n";
}
} else {
print_stats(" all sizes", @all_sizes);
print_stats(" all path sizes", @all_path_sizes);
print_stats(" tree sizes", @tree_sizes);
print_stats("tree path sizes", @tree_path_sizes);
print_stats(" depths", @depths);
}
