All the Perl that's Practical to Extract and Report

Profiling CGI Scripts with Devel::NYTProf

Mr. Muskrat on 2008-08-08T19:25:25

If you have not seen Devel::NYTProf yet then you must be living under a rock. I installed it on one of our development servers at work today (after watching the OSCON presentation. I have not had a chance to use it much but I am already deeply in love!

So I was reading through the docs and thinking "it works with mod_perl but what about normal CGI scripts?" Nothing that I have read indicated that it could not be done so I edited my Apache config to add the following (and restarted Apache of course): 

SetEnv PERL5OPT -d:NYTProf
SetEnv NYTPROF=file=/tmp/nytprof.out

I then accessed one of our CGI scripts and went to /tmp to create the HTML. However nytprof.out was not there. In its place was nytprof.out=!

So I changed the second line to be (and restarted Apache): 

SetEnv NYTPROF=file=/tmp/nytprof.out:
Yep, that second line really ends with a colon.

I hit the same CGI script and looked in /tmp. Yep, nytprof.out was there. Yay! (But I get "Unknown option:" in my error log.)

I think that I need to file a bug report (but have not yet because I do not know if it is an Apache bug, a Devel::NYTProf bug or simply user error). What do you think?

My next step was to run nytprofhtml. 

[mmusgrove@somebox tmp]$ nytprofhtml
Generating report...
Unable to open '/long/path/to/cgi-bin/security/Parser.yp' for reading: No such file or directory. Try running /opt/misc/bin/nytprofhtml in the same directory as you ran Devel::NYTProf, or ensure @INC is correct.

I look in /long/path/to/cgi-bin/security and sure enough there is not a Parser.yp file. The good news is that (most of) the HTML files were generated. *drool* They are absolutely gorgeous!

I pull up the index.html file in Firefox and scroll down a bit. What do I see but: 

230	0.00431	0.00002	line . block . sub	/long/path/to/cgi-bin/security/Parser.yp
I click on "line" and everything shown is from Template::Grammar. 
28	1	1	0.00033	0.00033	Template::Grammar::	__ANON__[Parser.yp:72]

I do not particularly care that I cannot drop down into the guts of Parser.yp. Yet I still cannot help but wonder if it is a bug in Devel::NYTProf or simply a by-product of how I got the profiling done... Anyone have any ideas?

shebang!

awwaiid on 2008-08-08T21:18:04

I've added it to the sheebang on a CGI a few times, such as: #!/usr/bin/perl -D:NYTProf

works pretty darn well :)

Something to look into then.

speters on 2008-08-10T15:39:25

I actually have never tried doing anything with Devel::NYTProf in CGI before I wrote the mod_perl handler. I am a bit surprised, though, to see that it wants a ":" after the file name though. What version of Devel::NYTProf are you using?

Re:Something to look into then.

Mr. Muskrat on 2008-08-11T14:17:26

package Devel::NYTProf;

our $VERSION = '2.02';