Measuring the Effect of Shared Objects

#!/usr/bin/perl

# Map from .so inodes to fnames
open(IN, q{locate .so | grep -v obj | xargs ls -li | grep -v -e '->'|}) || die;
while (<IN>) {
	@F = split;
	$fname{$F[0]} = $F[9];
}

# Get a list of all shared objects
open(IN, q{fstat -m | grep mmap | sed 's/rw$/ r/' | sort -u|}) || die;
while (<IN>) {
	@F = split;
	if (defined($fname{$F[5]})) {
		$used{$fname{$F[5]}}++;
		$size{$fname{$F[5]}} = $F[7];
		$unshared += $F[7];
		$mmap++;
	}
}

for $fname (keys %size) {
	$ssize += $size{$fname};
	$nobj++;
}

print "$nobj shared objects sharing $ssize bytes of memory with $mmap mappings. Memory required without sharing: $unshared bytes.\n";