Compress base files, use c-style strings in benchmarks.HEADmaster

9 files changed, 250 insertions, 346 deletions

diff --git a/bm/BM_HISTORY_1000_100.txt b/bm/BM_COMMIT_1000_100.txt
index 2885405..73a2b5a 100644
--- a/bm/BM_HISTORY_1000_100.txt
+++ b/bm/BM_COMMIT_1000_100.txt
@@ -1,60 +1,68 @@
 =============================================================
- HISTORY BENCHMARK: 1000 files (100 commits)
+ COMMIT BENCHMARK: 1000 files (100 commits)
+ CONDITIONS: Depth=2, Files Mod=0.5%, Line Mod=5%
+ INITIAL REPO SIZE: 17332 KB
 =============================================================
 
 SNAPSHOT: Commit #20
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.35s |                0.09s
+Time            |                0.29s |                0.03s
 Max RSS         |              0.02 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 1301 |                 2121
-Repo size       |             18868 KB |             22076 KB
+Inodes          |                 1300 |                 1425
+Repo size       |              6836 KB |              8296 KB
 -------------------------------------------------------------
 
 SNAPSHOT: Commit #40
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.46s |                0.11s
+Time            |                0.29s |                0.03s
 Max RSS         |              0.02 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 1341 |                 2929
-Repo size       |             19028 KB |             29136 KB
+Inodes          |                 1340 |                 1566
+Repo size       |              7332 KB |              9268 KB
 -------------------------------------------------------------
 
 SNAPSHOT: Commit #60
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.43s |                0.12s
+Time            |                0.35s |                0.03s
 Max RSS         |              0.02 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 1381 |                 3732
-Repo size       |             19188 KB |             36088 KB
+Inodes          |                 1381 |                 1706
+Repo size       |              7896 KB |             10236 KB
 -------------------------------------------------------------
 
 SNAPSHOT: Commit #80
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.45s |                0.08s
+Time            |                0.35s |                0.03s
 Max RSS         |              0.02 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 1421 |                 4538
-Repo size       |             19348 KB |             43104 KB
+Inodes          |                 1421 |                 1847
+Repo size       |              8456 KB |             11200 KB
 -------------------------------------------------------------
 
 SNAPSHOT: Commit #100
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.44s |                0.10s
+Time            |                0.35s |                0.03s
 Max RSS         |              0.02 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 1462 |                 5346
-Repo size       |             19512 KB |             49980 KB
+Inodes          |                 1462 |                 1987
+Repo size       |              9020 KB |             12168 KB
+-------------------------------------------------------------
+
+AFTER GIT GC
+-------------------------------------------------------------
+Final Size      |              9020 KB |              3812 KB
+Final Inodes    |                 1462 |                   41
 -------------------------------------------------------------
 
 TOTAL URN REBASES: 0
diff --git a/bm/BM_REBASE_1000_100.txt b/bm/BM_REBASE_1000_100.txt
deleted file mode 100644
index 7550570..0000000
--- a/bm/BM_REBASE_1000_100.txt
+++ /dev/null
@@ -1,61 +0,0 @@
-=============================================================
- REBASE BENCHMARK: 1000 files (100 commits)
- CONDITIONS: Depth=2, Files Mod=5%, Change=50%
-=============================================================
-
-SNAPSHOT: Commit #20
--------------------------------------------------------------
-METRIC          | URN                  | GIT                 
-----------------+----------------------+---------------------
-Time            |                0.65s |                0.08s
-Max RSS         |              0.02 MB |              0.01 MB
-Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 2272 |                 2282
-Repo size       |             38504 KB |             22700 KB
--------------------------------------------------------------
-
-SNAPSHOT: Commit #40
--------------------------------------------------------------
-METRIC          | URN                  | GIT                 
-----------------+----------------------+---------------------
-Time            |                0.59s |                0.08s
-Max RSS         |              0.02 MB |              0.01 MB
-Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 3332 |                 3322
-Repo size       |             59384 KB |             31188 KB
--------------------------------------------------------------
-
-SNAPSHOT: Commit #60
--------------------------------------------------------------
-METRIC          | URN                  | GIT                 
-----------------+----------------------+---------------------
-Time            |                0.57s |                0.08s
-Max RSS         |              0.02 MB |              0.01 MB
-Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 4392 |                 4362
-Repo size       |             80264 KB |             39676 KB
--------------------------------------------------------------
-
-SNAPSHOT: Commit #80
--------------------------------------------------------------
-METRIC          | URN                  | GIT                 
-----------------+----------------------+---------------------
-Time            |                0.57s |                0.08s
-Max RSS         |              0.02 MB |              0.01 MB
-Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 5452 |                 5402
-Repo size       |            101144 KB |             48156 KB
--------------------------------------------------------------
-
-SNAPSHOT: Commit #100
--------------------------------------------------------------
-METRIC          | URN                  | GIT                 
-----------------+----------------------+---------------------
-Time            |                0.57s |                0.08s
-Max RSS         |              0.02 MB |              0.01 MB
-Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                 6512 |                 6442
-Repo size       |            122024 KB |             56644 KB
--------------------------------------------------------------
-
-TOTAL URN REBASES: 4950
diff --git a/bm/BM_REPO_SIZE_200_20.txt b/bm/BM_REPO_SIZE_200_20.txt
index 69531c5..6c055bd 100644
--- a/bm/BM_REPO_SIZE_200_20.txt
+++ b/bm/BM_REPO_SIZE_200_20.txt
@@ -17,22 +17,22 @@ ACTION: Add
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.16s |                0.17s
+Time            |                0.17s |                0.17s
 Max RSS         |              0.02 MB |              0.00 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                  225 |                  360
-Repo size       |              3700 KB |              3348 KB
+Inodes          |                  225 |                  370
+Repo size       |              3608 KB |              3472 KB
 -------------------------------------------------------------
 
 ACTION: Commit
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.17s |                0.04s
+Time            |                0.17s |                0.05s
 Max RSS         |              0.02 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                  347 |                  397
-Repo size       |              4212 KB |              3496 KB
+Inodes          |                  352 |                  408
+Repo size       |              4140 KB |              3624 KB
 -------------------------------------------------------------
 
 ACTION: Status(Clean)
@@ -42,7 +42,7 @@ METRIC          | URN                  | GIT
 Time            |                0.10s |                0.01s
 Max RSS         |              0.02 MB |              0.00 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
-Inodes          |                  347 |                  397
-Repo size       |              4212 KB |              3496 KB
+Inodes          |                  352 |                  408
+Repo size       |              4140 KB |              3624 KB
 -------------------------------------------------------------
 
diff --git a/bm/BM_REPO_SIZE_5000_50.txt b/bm/BM_REPO_SIZE_5000_50.txt
index cd90798..e194153 100644
--- a/bm/BM_REPO_SIZE_5000_50.txt
+++ b/bm/BM_REPO_SIZE_5000_50.txt
@@ -6,7 +6,7 @@ ACTION: Status
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.26s |                0.00s
+Time            |                0.27s |                0.00s
 Max RSS         |              0.02 MB |              0.00 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
 Inodes          |                    6 |                   27
@@ -17,32 +17,32 @@ ACTION: Add
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                2.82s |                4.62s
+Time            |                2.90s |                4.54s
 Max RSS         |              0.02 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
 Inodes          |                 5055 |                 5284
-Repo size       |             89444 KB |             70360 KB
+Repo size       |             89996 KB |             69844 KB
 -------------------------------------------------------------
 
 ACTION: Commit
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                1.18s |                0.93s
+Time            |                1.60s |                0.93s
 Max RSS         |              0.03 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
 Inodes          |                 5264 |                 5342
-Repo size       |             91620 KB |             70592 KB
+Repo size       |             92172 KB |             70076 KB
 -------------------------------------------------------------
 
 ACTION: Status(Clean)
 -------------------------------------------------------------
 METRIC          | URN                  | GIT                 
 ----------------+----------------------+---------------------
-Time            |                0.34s |                0.10s
+Time            |                0.28s |                0.11s
 Max RSS         |              0.02 MB |              0.01 MB
 Page faults     |        Maj:0 / Min:0 |        Maj:0 / Min:0
 Inodes          |                 5264 |                 5342
-Repo size       |             91620 KB |             70592 KB
+Repo size       |             92172 KB |             70076 KB
 -------------------------------------------------------------
 
diff --git a/bm/bm_rebase.pl b/bm/bm_commit.pl
index e89e7f5..841325d 100644
--- a/bm/bm_rebase.pl
+++ b/bm/bm_commit.pl
@@ -1,4 +1,6 @@
 #!/usr/bin/perl
+# Usage: perl bm_commit.pl <file_count> <depth> <total_commits> <file_perc> <line_perc>
+# Example: perl bm_commit.pl 100 5 50 10 2
 use strict;
 use warnings;
 use File::Copy;
@@ -9,9 +11,9 @@ 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 $change_perc) {
-	die "Usage: perl bm_rebase.pl <file_count> <depth> <total_commits> <file_perc> <change_perc>\n";
+my ($files, $depth, $total_commits, $file_perc, $line_perc) = @ARGV;
+if (!defined $line_perc) {
+	die "Usage: perl bm_commit.pl <file_count> <depth> <total_commits> <file_perc> <line_perc>\n";
 }
 
 my $base_dir = getcwd();
@@ -21,12 +23,11 @@ my $bm_repo  = "sandbox";
 
 my $sample_rate = int($total_commits / 5) || 1;
 my %results;
+my %final_stats = ( URN => { size => "N/A", inodes => 0 }, GIT => { size => "N/A", inodes => 0 } );
 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;
@@ -38,35 +39,56 @@ sub get_size {
 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 $count || 0;
+	my %inodes;
+	find(sub { my @s = lstat($_); $inodes{$s[1]} = 1 if @s; }, $dir);
+	return scalar(keys %inodes);
 }
 
 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;
+		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++;
-		}
+		$rebase_count++ if exists $last_base_hashes{$path} && $last_base_hashes{$path} ne $b_hash;
 		$last_base_hashes{$path} = $b_hash;
 	}
 	close($fh);
 }
 
-sub run_rebase_benchmark {
+sub generate_surgical_line {
+	my ($original_line) = @_;
+	my @types = qw(int char float double bool uint32_t);
+	my @vars  = qw(offset limit buffer status count ptr index);
+	
+	$original_line =~ /^(\s*)/;
+	my $indent = $1 || "    ";
+	
+	my $type = $types[rand @types];
+	my $var  = $vars[rand @vars] . "_" . int(rand(100));
+	my $val  = int(rand(1000));
+	
+	my $new_line = "$indent$type $var = $val;\n";
+	
+	# Byte matching: pad with spaces before the newline to keep file size identical
+	my $target_len = length($original_line);
+	if (length($new_line) < $target_len) {
+		substr($new_line, -1, 0, " " x ($target_len - length($new_line)));
+	} elsif (length($new_line) > $target_len) {
+		$new_line = substr($new_line, 0, $target_len - 2) . ";\n";
+	}
+	
+	return $new_line;
+}
+
+sub run_commit_benchmark {
 	my ($tool_name) = @_;
-	print ">>> Starting REBASE BENCHMARK: $tool_name\n";
+	print ">>> Starting COMMIT 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); }
+	$initial_repo_size = get_size($bm_repo) if $initial_repo_size eq "0 KB";
 	
 	chdir($bm_repo) or die $!;
 
@@ -86,36 +108,31 @@ sub run_rebase_benchmark {
 	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);
+			open(my $fh, '<', $target) or die "Read fail: $target - $!";
+			my @lines = <$fh>;
+			close($fh);
+
+			# Find lines that are simple variable assignments to maintain surgical diffs
+			my @eligible = grep { $lines[$_] =~ /^\s*\w+ \w+ = \d+;/ } (0 .. $#lines);
+
+			if (@eligible) {
+				# Calculate count based on percentage of eligible lines
+				my $to_mod = int(scalar(@eligible) * ($line_perc / 100));
+				$to_mod = 1 if $to_mod == 0; 
+
+				my @indices = (sort { rand() <=> rand() } @eligible)[0 .. $to_mod - 1];
+
+				for my $idx (@indices) {
+					next unless defined $idx;
+					$lines[$idx] = generate_surgical_line($lines[$idx]);
+				}
+
+				open(my $out, '>', $target) or die "Write fail: $target - $!";
+				print $out join('', @lines);
+				close($out);
+				utime(undef, undef, $target);
+			}
 		}
 
 		my $cmd = ($tool_name eq "URN") 
@@ -124,10 +141,7 @@ sub run_rebase_benchmark {
 
 		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();
-			}
+			track_rebases() if $tool_name eq "URN";
 
 			my ($real, $rss, $maj, $min) = (0, 0, 0, 0);
 			$real = $1 if $raw_output =~ /(\d+\.\d+)\s+real/;
@@ -138,7 +152,7 @@ sub run_rebase_benchmark {
 			my $meta = ($tool_name eq "URN") ? ".urn" : ".git";
 			$results{$i}{$tool_name} = {
 				real   => $real . "s",
-				rss    => $rss,
+				rss    => $rss || "0 MB",
 				faults => "Maj:$maj / Min:$min",
 				inodes => count_inodes($meta),
 				size   => get_size($meta),
@@ -149,24 +163,35 @@ sub run_rebase_benchmark {
 			track_rebases() if $tool_name eq "URN";
 		}
 	}
+
+	system("git gc --prune=now --quiet") if $tool_name eq "GIT";
+
+	my $final_meta = ($tool_name eq "URN") ? ".urn" : ".git";
+	$final_stats{$tool_name} = {
+		size   => get_size($final_meta) || "0 KB",
+		inodes => count_inodes($final_meta) || 0,
+	};
+
 	chdir($base_dir);
+	remove_tree($bm_repo);
 }
 
-$rebase_count = 0;
-%last_base_hashes = ();
-run_rebase_benchmark("URN");
-run_rebase_benchmark("GIT");
+run_commit_benchmark("URN");
+run_commit_benchmark("GIT");
 
-my $out_file = "BM_REBASE_${files}_${total_commits}.txt";
+my $out_file = "BM_COMMIT_${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 " COMMIT BENCHMARK: $files files ($total_commits commits)\n";
+print $res " CONDITIONS: Depth=$depth, Files Mod=$file_perc%, Line Mod=$line_perc%\n";
+print $res " INITIAL REPO SIZE: $initial_repo_size\n";
 print $res "=============================================================\n\n";
 
 foreach my $i (sort { $a <=> $b } keys %results) {
 	my $u = $results{$i}{"URN"};
 	my $g = $results{$i}{"GIT"};
+	next unless defined $u && defined $g;
+
 	print $res "SNAPSHOT: Commit #$i\n";
 	print $res "-------------------------------------------------------------\n";
 	printf $res "%-15s | %-20s | %-20s\n", "METRIC", "URN", "GIT";
@@ -178,7 +203,15 @@ foreach my $i (sort { $a <=> $b } keys %results) {
 	printf $res "%-15s | %20s | %20s\n", "Repo size", $u->{size}, $g->{size};
 	print $res "-------------------------------------------------------------\n\n";
 }
+
+print $res "AFTER GIT GC\n";
+print $res "-------------------------------------------------------------\n";
+printf $res "%-15s | %20s | %20s\n", "Final Size", $final_stats{URN}{size}, $final_stats{GIT}{size};
+printf $res "%-15s | %20s | %20s\n", "Final Inodes", $final_stats{URN}{inodes}, $final_stats{GIT}{inodes};
+print $res "-------------------------------------------------------------\n\n";
+
 print $res "TOTAL URN REBASES: $rebase_count\n";
 close($res);
 
-exec "less $out_file";
+my $pager = $ENV{PAGER} || 'less';
+system("$pager $out_file");
diff --git a/bm/bm_history.pl b/bm/bm_history.pl
deleted file mode 100644
index 5f2ea4a..0000000
--- a/bm/bm_history.pl
+++ /dev/null
@@ -1,152 +0,0 @@
-#!/usr/bin/perl
-use strict;
-use warnings;
-use File::Spec;
-use File::Path qw(remove_tree);
-use File::Find;
-use Cwd qw(getcwd abs_path);
-
-my ($files, $depth, $total_commits) = @ARGV;
-if (!defined $files || !defined $depth || !defined $total_commits) {
-	die "Usage: perl bm_history.pl <file_count> <depth> <total_commits>\n";
-}
-
-my $base_dir = getcwd();
-my $urn_bin  = abs_path(File::Spec->catfile("..", "urn")); 
-my $seed_bin = abs_path("seed.pl");
-my $bm_repo  = "bm_repo";
-
-my $sample_rate = int($total_commits / 5) || 1;
-my %results;
-
-my $rebase_count = 0;
-my %last_base_hashes;
-
-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_history_benchmark {
-	my ($tool_name) = @_;
-	print ">>> Starting History Benchmark: $tool_name\n";
-
-	remove_tree($bm_repo) if -d $bm_repo;
-	system("perl $seed_bin $files $depth > /dev/null 2>&1");
-	
-	chdir($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)/ }, ".");
-
-	for my $i (1 .. $total_commits) {
-		my $to_modify = int($files * 0.02) || 1;
-		for (1 .. $to_modify) {
-			my $target = $file_list[rand @file_list];
-			if (open(my $fh, '>>', $target)) {
-				print $fh "Churn $i\n";
-				close($fh);
-			}
-		}
-
-		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) {
-			# Capture hardware metrics via /usr/bin/time -l
-			my $stats = `/usr/bin/time -l sh -c "$cmd" 2>&1 > /dev/null`;
-			
-			my ($real, $rss, $maj, $min) = (0, 0, 0, 0);
-			if ($stats =~ /(\d+\.\d+)\s+real/) { $real = $1; }
-			if ($stats =~ /(\d+)\s+maximum resident set size/) { $rss = sprintf("%.2f MB", $1 / 1024 / 1024); }
-			if ($stats =~ /(\d+)\s+page reclaims/) { $min = $1; }
-			if ($stats =~ /(\d+)\s+page faults/) { $maj = $1; }
-
-			if ($tool_name eq "URN") { track_rebases(); }
-
-			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");
-			if ($tool_name eq "URN") { track_rebases(); }
-		}
-	}
-	chdir($base_dir);
-	remove_tree($bm_repo);
-}
-
-$rebase_count = 0;
-%last_base_hashes = ();
-run_history_benchmark("URN");
-run_history_benchmark("GIT");
-
-my $out_file = "BM_HISTORY_${files}_${total_commits}.txt";
-open(my $res, '>', $out_file) or die $!;
-print $res "=============================================================\n";
-print $res " HISTORY BENCHMARK: $files files ($total_commits commits)\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);
-
-my $pager = $ENV{PAGER} || 'less';
-exec $pager, $out_file;
-
diff --git a/bm/bm_size.pl b/bm/bm_size.pl
index d21cfd6..d3d10d7 100644
--- a/bm/bm_size.pl
+++ b/bm/bm_size.pl
@@ -13,7 +13,7 @@ if (!defined $files || !defined $depth) {
 my $base_dir = getcwd();
 my $urn_bin  = abs_path(File::Spec->catfile("..", "urn")); 
 my $seed_bin = abs_path("seed.pl");
-my $bm_repo  = "bm_repo";
+my $bm_repo  = "sandbox";
 
 my %results;
 my @actions = qw(Status Add Commit Status(Clean));
diff --git a/bm/seed.pl b/bm/seed.pl
index 81c70dd..fdf3884 100644
--- a/bm/seed.pl
+++ b/bm/seed.pl
@@ -13,20 +13,53 @@ if (!defined $total_files || !defined $max_depth) {
 my $target_root = "sandbox";
 my $files_created = 0;
 
-# Helper to generate random "code-like" text
 sub generate_content {
-	my $size_kb = 5 + int(rand(21)); # 5-25 KB
-	my $bytes = $size_kb * 1024;
+	my $size_kb = 5 + int(rand(21));
+	my $target_bytes = $size_kb * 1024;
 	my $content = "";
-	my @chars = ('a'..'z', 'A'..'Z', '0'..'9');
-	
-	while (length($content) < $bytes) {
-		my $line_len = 20 + int(rand(60));
-		$content .= "\t" if rand() > 0.5; # Random indentation
-		for (1..$line_len) { $content .= $chars[rand @chars]; }
-		$content .= (rand() > 0.7) ? " " : ""; # Random spaces
-		$content .= "\n";
+
+	my @types    = qw(int char void float double uint32_t bool);
+	my @ops      = qw(= += -= == != < >);
+	my @vars     = qw(count index status buffer ptr limit offset);
+
+	$content .= "#include <stdio.h>\n#include <stdlib.h>\n\n";
+
+	while (length($content) < $target_bytes) {
+		my $roll = rand();
+
+		if ($roll < 0.15) {
+			# Function definition (no indent)
+			my $type = $types[rand @types];
+			my $name = "process_data_" . int(rand(100));
+			$content .= "\n$type $name() {\n";
+		} 
+		elsif ($roll < 0.60) {
+			# Standard assignment (1 tab)
+			my $type = $types[rand @types];
+			my $var  = $vars[rand @vars] . "_" . int(rand(50));
+			my $val  = int(rand(1000));
+			$content .= "\t$type $var = $val;\n";
+		} 
+		elsif ($roll < 0.80) {
+			# If block with nested logic (1-2 tabs)
+			my $var = $vars[rand @vars];
+			$content .= "\tif ($var > " . int(rand(100)) . ") {\n";
+			$content .= "\t\t$var " . $ops[rand @ops] . " 1;\n";
+			$content .= "\t\treturn $var;\n";
+			$content .= "\t}\n";
+		} 
+		elsif ($roll < 0.95) {
+			# Closing brace (no indent)
+			$content .= "}\n\n";
+		}
+		else {
+			# Comment line (1 tab)
+			$content .= "\t/* Update state " . int(rand(1000)) . " */\n";
+		}
 	}
+	
+	# Cleanup: Ensure we close the last function block
+	$content .= "\n}\n" unless $content =~ /}\n\s*$/;
 	return $content;
 }
 
@@ -34,8 +67,6 @@ sub seed_tree {
 	my ($current_path, $depth, $files_left) = @_;
 	return if $files_left <= 0;
 
-	# Determine how many files to put in THIS directory
-	# Heuristic: Spread them out, but ensure at least 1 if depth remains
 	my $files_here = ($depth == $max_depth) 
 		? $files_left 
 		: int($files_left / ($max_depth - $depth + 1)) + int(rand(3));
@@ -45,20 +76,20 @@ sub seed_tree {
 	make_path($current_path) unless -d $current_path;
 
 	for (1..$files_here) {
-		my $filename = "file_" . sprintf("%04d", ++$files_created) . ".txt";
+		my $filename = "src_" . sprintf("%04d", ++$files_created) . ".c";
 		my $full_path = File::Spec->catfile($current_path, $filename);
-		open(my $fh, '>', $full_path) or die $!;
+		open(my $fh, '>', $full_path) or die "Could not open $full_path: $!";
 		print $fh generate_content();
 		close($fh);
 	}
 
-	# If we have depth and files remaining, go deeper
 	if ($depth < $max_depth && ($files_left - $files_here) > 0) {
-		my $next_dir = File::Spec->catdir($current_path, "depth_" . ($depth + 1));
+		my $next_dir = File::Spec->catdir($current_path, "subdir_" . ($depth + 1));
 		seed_tree($next_dir, $depth + 1, $files_left - $files_here);
 	}
 }
 
-print "Seeding $total_files files across $max_depth levels...\n";
+print "Seeding $total_files files (C-style) with tab indents...\n";
 seed_tree($target_root, 1, $total_files);
-print "Done. Created $files_created files in '$target_root'.\n";
+print "Success. Created $files_created files in '$target_root'.\n";
+
diff --git a/urn b/urn
index c8ddbce..5fe2f8a 100644
--- a/urn
+++ b/urn
@@ -3,6 +3,8 @@
 use strict;
 use warnings;
 use IO::Handle;
+use IO::Compress::Gzip qw(gzip $GzipError);
+use IO::Uncompress::Gunzip qw(gunzip $GunzipError);
 use File::Path qw(make_path);
 use File::Copy qw(copy);
 use File::Basename;
@@ -26,6 +28,10 @@ use constant CHUNK_LEN  => 8192;
 use constant MEM_LIMIT  => 64 * 1024 * 1024;
 use constant IO_LAYER   => ":raw:perlio(layer=" . CHUNK_LEN . ")";
 
+use constant GZIP_LEVEL       =>   6;
+use constant GZIP_THRESHOLD   => 256;
+use constant REBASE_THRESHOLD => 1.4;
+
 Getopt::Long::Configure("bundling");
 
 my $cmd = shift @ARGV // '';
@@ -261,6 +267,8 @@ sub run_commit {
 	my $use_disk_patch = 0;
 	my ($pt_fh, $pt_path);
 
+	my $tar_size = 0;
+
 	my ($tmp_idx_fh, $tmp_idx_path) = tempfile(DIR => TMP_DIR, UNLINK => 0);
 	binmode $tmp_idx_fh, ":raw";
 
@@ -276,26 +284,26 @@ sub run_commit {
 			$out_c = $out_s;
 			$out_b = $out_s;
 
-			my $obj_path = get_obj_path($out_b);
 			my $stg_file = File::Spec->catfile(TMP_DIR, $out_p);
-			if (!-e $obj_path) {
-				rename($stg_file, $obj_path) or copy($stg_file, $obj_path);
-			}
+			store_base_file($stg_file, $out_b);
 			$idx = $it_idx->();
 		}
 		elsif ($cmp == 0) { # Modified or Unchanged
 			($out_p, $out_s, $out_m, $out_z) = ($idx->{path}, $idx->{s_hash}, $idx->{mtime}, $idx->{size});
 
 			if ($idx->{s_hash} ne ($idx->{c_hash} // "-")) {
-				my $base_obj = get_obj_path($old->{hash});
+				my $base_obj = get_base_file($old->{hash});
 				my $stg_file = File::Spec->catfile(TMP_DIR, $out_p);
 
 				my $patch = (-T $stg_file) 
 					? qx(diff '$base_obj' '$stg_file')
 					: make_bin_patch($stg_file, $base_obj);
 
-				if (defined $patch && length($patch) <= $out_z) {
-					if (!$use_disk_patch && ($patch_mem_size + length($patch)) > MEM_LIMIT) {
+				my $patch_len = length($patch);
+				$tar_size += $patch_len;
+
+				if (defined $patch && $patch_len <= ($out_z * REBASE_THRESHOLD)) {
+					if (!$use_disk_patch && ($patch_mem_size + $patch_len) > MEM_LIMIT) {
 						($pt_fh, $pt_path) = tempfile(DIR => TMP_DIR, UNLINK => 0);
 						my $tar = Archive::Tar->new;
 						$tar->add_data($_, $patches{$_}) for keys %patches;
@@ -309,16 +317,13 @@ sub run_commit {
 						$tar->write($pt_path);
 					} else {
 						$patches{"$out_p.patch"} = $patch;
-						$patch_mem_size += length($patch);
+						$patch_mem_size += $patch_len;
 					}
 					$out_b = $old->{hash};
 					unlink($stg_file); 
 				} else {
 					$out_b = $out_s;
-					my $obj_path = get_obj_path($out_b);
-					if (!-e $obj_path) {
-						rename($stg_file, $obj_path) or copy($stg_file, $obj_path);
-					}
+					store_object_file($stg_file, $out_b);
 				}
 				$out_c = $out_s;
 			} else {
@@ -364,7 +369,7 @@ sub run_commit {
 		my $tar = Archive::Tar->new;
 		if ($use_disk_patch) { $tar->read($pt_path); unlink $pt_path; }
 		$tar->add_data($_, $patches{$_}) for keys %patches;
-		$tar->write($bundle_tmp, COMPRESS_GZIP);
+		$tar->write($bundle_tmp, ($tar_size >= GZIP_THRESHOLD ? GZIP_LEVEL : 0));
 		$patch_bundle_hash = hash_file_content($bundle_tmp);
 		rename($bundle_tmp, get_obj_path($patch_bundle_hash));
 	}
@@ -437,11 +442,9 @@ sub run_show {
 	open(my $pipe, "| $pager") or die "Can't pipe to $pager: $!";
 	my $old_fh = select($pipe);
 
-	# 2. Use existing logic to get the content
 	my $v = get_file_version($rev_id, $file_path);
 	die "Error: Could not resolve '$file_path' at revision $rev_id.\n" unless defined $v;
 
-	# 3. Output content
 	if (ref($v) eq 'SCALAR') {
 		binmode STDOUT, ":raw";
 		print $$v;
@@ -493,7 +496,7 @@ sub run_diff {
 			}
 		}
 	} else {
-		# Full Tree Walk
+		# Full tree walk
 		my $s_id = (lc($src // '') eq 'head') ? read_head() : ($src // '');
 		my $th; if (open my $rf, '<', File::Spec->catfile(REV_DIR, $s_id)) {
 			while (<$rf>) { $th = $1 if /^tree:(.*)$/ } close $rf;
@@ -815,7 +818,7 @@ sub is_revision {
 sub get_file_version {
 	my ($source, $path) = @_;
 
-	# Handle Workspace
+	# Handle workspace
 	if (!defined $source) {
 		return undef unless -e $path;
 		if ((-s $path // 0) > MEM_LIMIT) {
@@ -828,7 +831,7 @@ sub get_file_version {
 		return \$data;
 	}
 
-	# Resolve Revision
+	# Resolve revision
 	my $rev_id = (lc($source) eq 'head') ? read_head() : $source;
 	my $rev_file = File::Spec->catfile(REV_DIR, $rev_id);
 	return undef unless -f $rev_file;
@@ -852,10 +855,10 @@ sub get_file_version {
 	}
 	return undef unless $node;
 
-	my $obj_path = get_obj_path($node->{hash} // '');
+	my $obj_path = get_base_file($node->{hash});
 	return undef unless -f $obj_path;
 
-	# Extract Base Object to Temp File
+	# Extract base object to temp file
 	my ($tfh, $tpath) = tempfile(DIR => TMP_DIR, UNLINK => 1);
 	binmode $tfh, IO_LAYER;
 	
@@ -863,9 +866,9 @@ sub get_file_version {
 	binmode $ofh, IO_LAYER;
 	while (read($ofh, my $buf, CHUNK_LEN)) { print $tfh $buf; }
 	close $ofh;
-	close $tfh;
+	close $tfh;	
 
-	# Apply Patch via Streaming Bundle
+	# Apply patch via streaming bundle
 	if ($patch_bundle_hash) {
 		my $bundle_path = get_obj_path($patch_bundle_hash);
 		if (-f $bundle_path && -s $bundle_path > 0) {
@@ -891,7 +894,7 @@ sub get_file_version {
 		}
 	}
 
-	# Final Output decision based on result size
+	# Final output decision based on result size
 	if ((-s $tpath // 0) > MEM_LIMIT) {
 		return $tpath; 
 	} else {
@@ -900,3 +903,45 @@ sub get_file_version {
 	}
 }
 
+sub get_base_file {
+	my ($obj_hash) = @_;
+	my $obj_path = get_obj_path($obj_hash);
+	return undef unless -f $obj_path;
+
+	# Peek at the first two bytes for GZIP header
+	open my $fh, '<:raw', $obj_path or return $obj_path;
+	read($fh, my $header, 2);
+	close $fh;
+
+	# If it's not gzipped, return the original path in the object store
+	return $obj_path unless (defined $header && $header eq "\x1f\x8b");
+
+	# If gzipped, decompress to a temporary file in the staging area
+	my ($tfh, $tpath) = tempfile(DIR => TMP_DIR, UNLINK => 1);
+	close $tfh;
+
+	gunzip $obj_path => $tpath 
+		or die "Failed to decompress base $obj_path: $GunzipError";
+
+	return $tpath;
+}
+
+sub store_base_file {
+	my ($stg_file, $obj_hash) = @_;
+	my $obj_path = get_obj_path($obj_hash);
+
+	# If the object already exists, we don't need to do anything
+	return $obj_path if -e $obj_path;
+
+	if (!-l $stg_file && -s $stg_file > GZIP_THRESHOLD) {
+		gzip $stg_file => $obj_path, Level => GZIP_LEVEL
+			or die "gzip failed for $obj_path: $GzipError";
+		unlink($stg_file);
+	}
+	else {
+		rename($stg_file, $obj_path) or copy($stg_file, $obj_path);
+	}
+
+	return $obj_path;
+}
+