"benchmarking" memory usage

salva has asked for the wisdom of the Perl Monks concerning the following question:

I would like to do something like that:

use Memchmark qw(cmpthese);

my @data = 1..$ARGV[0];
cmpthese(-1, { foo => sub { my @out = foo(@data) },
               bar => sub { my @out = bar(@data) } });
[download]

but unfortunately, Memchmark doesn't exist yet... so my question is: how can memory usage be measured?

BTW, I don't need accurate numbers, an error around 25% could be admissible. I don't need it to be portable either, it should just work on Linux.

update: I have just uploaded Memchmark to CPAN.

Comment on "benchmarking" memory usage Select or Download Code

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Re: "benchmarking" memory usage by Zaxo (Archbishop) on May 30, 2005 at 19:54 UTC
Build a perl with DEBUGGING defined. That will allow you to use the -Dm run option, which tracks all memory allocations. See perlrun. After Compline, Zaxo	[reply]
Re: "benchmarking" memory usage by dug (Chaplain) on May 30, 2005 at 19:56 UTC
Devel::Size might be of use. -- Douglas Hunter	[reply]
Re: "benchmarking" memory usage by mda2 (Hermit) on May 30, 2005 at 20:18 UTC
Recently I identified one memory leak on my webservice daemon (pure perl), and find resources to do it... Check modules Find::Globals, Devel::Size. These modules work on solaris box, but on linux other modules area available with some libraries dependencies (Devel::Leak, Devel::LeakTrace), but I don't used it. My compare with Devel::FindGlobals are text based: use Devel::FindGlobals; open(D, "> $0." . time() ); print D "Globals: ", print_globals_sizes(), "\n"; close(D); __END__ Globals: Name of SCALAR variable Size Total Size ================================================================= $AutoLoader::AUTOLOAD 48 48 $AutoLoader::VERSION 29 29 $Benchmark::VERSION 20 20 $Benchmark::cache 16 16 ... cut ... $Carp::Verbose 16 16 $Class::ReturnValue::() 28 28 $Class::ReturnValue::VERSION 29 29 $Click21::Dist::VERSION 20 20 $Click21::Dominio 16 1625 $Click21::Dominio::VERSION 20 20 ... cut ... [download] After make two logs on pré-defined points, make a diff to identify size changes. ............. -- Marco Antonio Rio-PM	[reply] [d/l]
Re: "benchmarking" memory usage by mirod (Canon) on May 30, 2005 at 21:09 UTC
AFAIK Perl does not give back memory to the OS. So on Linux, if you put your code to benchmark in 2 different scripts, for each of them, just before exiting, you can get the memory used by your code in `/proc/$$/status`.	[reply]
Re^2: "benchmarking" memory usage by salva (Canon) on May 30, 2005 at 21:14 UTC
actually, I was thinking about a similar aproach but using fork and Proc::ProcessTable --> Memchmark	[reply]
Re^2: "benchmarking" memory usage by Fletch (Bishop) on May 31, 2005 at 14:08 UTC
This came up recently, but depending on the OS and your `malloc(3)` implementation you may see your `perl` process size shrink when `free(3)` gets called or you might not. Might be interesting to see a table of `$^O` / `$Config{usemymalloc}` / "will my process shrink?" across some different combinations. -- We're looking for people in ATL	[reply] [d/l] [select]
Re: "benchmarking" memory usage by bofh_of_oz (Hermit) on May 30, 2005 at 20:22 UTC
UPDATE: removed my post as irrelevant to the original question... -------------------------------- An idea is not responsible for the people who believe in it...	[reply]