Re: simple profiling capability

[Jonathan Vanasco <suppressed>]

i'm just tossing this idea out...

1) have a profiler package that handles all the logging, etc - and  
uses a constant

	package MyApp:::Profiler;
	use constant DO_PROFILE=> 1;
	sub profile {
		my ( $marker )= @_ ;
		#log;
	}
	1;

2) in your app code, do this:
	MyApp:::Profiler::DO_PROFILE && MyApp:::Profiler::profile( 'some  
identifier' );

My rationale:
	a) creating the namespace / etc means you can just wrap whatever  
method you want cleanly
	b) mp will optimize away the calls to profile if you start the  
server with DO_PROFILE set to 0 -- this way you don't have to deal  
with a performance hit in production and can leave the calls intact  
as-is.

in terms of actually recording...

i'd probably stack everything into a local variable as an array ;  
then id drop in a cleanup handler that calls a function to write it  
to disk or memory somehow... you'd have to have a reset within the  
package that clears out the var too

	my 	@profile;
	sub profile {
		my ( $marker )= @_ ;
		push @profile , $marker;
	}
	sub cleanup {
		# record
			record( suppressed );
		# reset
		@profile= ();
	}

in any event , the bulk of my suggestions are this:
	1- there's no reason to continually write to disk or shared mem , or  
call misc functions  ( unless you're profiling in-time ).  just store  
that stuff in a perl structure and dump 1x.
	2- use the optimize-away hack with constants to quickly turn off  
your debug code



On Nov 12, 2007, at 10:42 AM, E R wrote:

> Hi,
>
> I have the need for a simple profiling capability for mod_perl  
> applications.
> At a few (< 50) points in my code I want to call something like:
>
> $profiler->mark("some identifier");
>
> and increment the counter for "some identifier". Later I want to be  
> able to get
> (through a web page) a summary (grouped by identifiers) of all the
> profiling calls
> made (of course, made by all Apache child processes.) For instance,  
> if I want
> to profile the number of times a particular subroutine was called,  
> I would use:
>
> sub mysubroutine {
>   $profiler->mark("in mysubroutine");
>   ...
> }
>
> This is very similar to logging, except for the summary part. Does  
> anyone
> have ideas of a good way to implement this? Shared memory? An external
> daemon to record these calls? Has someone already implemented this?
> Robust and simple are good.
>
> Thanks,
>
> ER