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DBI::ProfileDumper::ApUser(Contributed Perl DocumDBI::ProfileDumper::Apache(3)

NAME
       DBI::ProfileDumper::Apache - capture DBI profiling data from
       Apache/mod_perl
SYNOPSIS
       Add this line to your httpd.conf:
         PerlSetEnv DBI_PROFILE 2/DBI::ProfileDumper::Apache
       (If you're using mod_perl2, see "When using mod_perl2" for some
       additional notes.)
       Then restart your server.  Access the code you wish to test using a web
       browser, then shutdown your server.  This will create a set of
       dbi.prof.* files in your Apache log directory.
       Get a profiling report with dbiprof:
         dbiprof /path/to/your/apache/logs/dbi.prof.*
       When you're ready to perform another profiling run, delete the old
       files and start again.
DESCRIPTION
       This module interfaces DBI::ProfileDumper to Apache/mod_perl.  Using
       this module you can collect profiling data from mod_perl applications.
       It works by creating a DBI::ProfileDumper data file for each Apache
       process.  These files are created in your Apache log directory.  You
       can then use the dbiprof utility to analyze the profile files.
USAGE
   LOADING THE MODULE
       The easiest way to use this module is just to set the DBI_PROFILE
       environment variable in your httpd.conf:
         PerlSetEnv DBI_PROFILE 2/DBI::ProfileDumper::Apache
       The DBI will look after loading and using the module when the first DBI
       handle is created.
       It's also possible to use this module by setting the Profile attribute
       of any DBI handle:
         $dbh->{Profile} = "2/DBI::ProfileDumper::Apache";
       See DBI::ProfileDumper for more possibilities, and DBI::Profile for
       full details of the DBI's profiling mechanism.
   WRITING PROFILE DATA
       The profile data files will be written to your Apache log directory by
       default.
       The user that the httpd processes run as will need write access to the
       directory.  So, for example, if you're running the child httpds as user
       'nobody' and using chronolog to write to the logs directory, then
       you'll need to change the default.
       You can change the destination directory either by specifying a "Dir"
       value when creating the profile (like "File" in the DBI::ProfileDumper
       docs), or you can use the "DBI_PROFILE_APACHE_LOG_DIR" env var to
       change that. For example:
         PerlSetEnv DBI_PROFILE_APACHE_LOG_DIR /server_root/logs
       When using mod_perl2
       Under mod_perl2 you'll need to either set the
       "DBI_PROFILE_APACHE_LOG_DIR" env var, or enable the mod_perl2
       "GlobalRequest" option, like this:
         PerlOptions +GlobalRequest
       to the global config section you're about test with
       DBI::ProfileDumper::Apache.  If you don't do one of those then you'll
       see messages in your error_log similar to:
         DBI::ProfileDumper::Apache on_destroy failed: Global $r object is not available. Set:
           PerlOptions +GlobalRequest in httpd.conf at ..../DBI/ProfileDumper/Apache.pm line 144
       Naming the files
       The default file name is inherited from DBI::ProfileDumper via the
       filename() method, but DBI::ProfileDumper::Apache appends the parent
       pid and the current pid, separated by dots, to that name.
       Silencing the log
       By default a message is written to STDERR (i.e., the apache error_log
       file) when flush_to_disk() is called (either explicitly, or implicitly
       via DESTROY).
       That's usually very useful. If you don't want the log message you can
       silence it by setting the "Quiet" attribute true.
         PerlSetEnv DBI_PROFILE 2/DBI::ProfileDumper::Apache/Quiet:1
         $dbh->{Profile} = "!Statement/DBI::ProfileDumper/Quiet:1";
         $dbh->{Profile} = DBI::ProfileDumper->new(
             Path => [ '!Statement' ]
             Quiet => 1
         );
   GATHERING PROFILE DATA
       Once you have the module loaded, use your application as you normally
       would.  Stop the webserver when your tests are complete.  Profile data
       files will be produced when Apache exits and you'll see something like
       this in your error_log:
         DBI::ProfileDumper::Apache writing to /usr/local/apache/logs/dbi.prof.2604.2619
       Now you can use dbiprof to examine the data:
         dbiprof /usr/local/apache/logs/dbi.prof.2604.*
       By passing dbiprof a list of all generated files, dbiprof will
       automatically merge them into one result set.  You can also pass
       dbiprof sorting and querying options, see dbiprof for details.
   CLEANING UP
       Once you've made some code changes, you're ready to start again.
       First, delete the old profile data files:
         rm /usr/local/apache/logs/dbi.prof.*
       Then restart your server and get back to work.
OTHER ISSUES
   Memory usage
       DBI::Profile can use a lot of memory for very active applications
       because it collects profiling data in memory for each distinct query
       run.  Calling "flush_to_disk()" will write the current data to disk and
       free the memory it's using. For example:
         $dbh->{Profile}->flush_to_disk() if $dbh->{Profile};
       or, rather than flush every time, you could flush less often:
         $dbh->{Profile}->flush_to_disk()
           if $dbh->{Profile} and ++$i % 100;
AUTHOR
       Sam Tregar <sam AT tregar.com>
COPYRIGHT AND LICENSE
       Copyright (C) 2002 Sam Tregar
       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl 5 itself.

perl v5.16.3                      2013-04-04     DBI::ProfileDumper::Apache(3)