DBI::Pr...:Apache(3)

💖 DBI::ProfileDumper::Apache 💖

okay bestie, so this is a page from the User Contributed Perl Documentation collection, and it's literally called DBI::ProfileDumper::Apache — it's giving "capture DBI profiling data from Apache/mod_perl" and honestly? slay. 🌸

---

✨ NAME ✨

DBI::ProfileDumper::Apache — bestie, this module captures DBI profiling data from Apache/mod_perl. no cap. 🎀

---

🦋 SYNOPSIS 🦋

okay so step one, you're gonna add this line to your httpd.conf:

PerlSetEnv DBI_PROFILE 2/DBI::ProfileDumper::Apache

💅 psst — if you're using mod_perl2, go peek at the "When using mod_perl2" bit below for some extra notes, iykyk.

Then restart your server. Hit up the code you wanna test with a web browser, then shut your server down. This will create a whole little squad of dbi.prof.* files in your Apache log directory. 🫶

Get a profiling report with dbiprof:

dbiprof /path/to/your/apache/logs/dbi.prof.*

And when you're ready to do another profiling run, delete the old files and start again. fresh start energy ✨

---

💜 DESCRIPTION 💜

This module interfaces DBI::ProfileDumper to Apache/mod_perl. Using it, you can collect profiling data from mod_perl applications. The way it works: it makes a DBI::ProfileDumper data file for each Apache process 🌈. These files get created in your Apache log directory, and then you can use the dbiprof utility to analyze the profile files. iconic behavior, honestly.

---

🔥 USAGE 🔥

🍓 LOADING THE MODULE 🍓

The easiest way to use this module is literally just to set the DBI_PROFILE environment variable in your httpd.conf:

PerlSetEnv DBI_PROFILE 2/DBI::ProfileDumper::Apache

The DBI will handle loading and using the module when the first DBI handle is created. no effort required, main character energy 😌

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. go read those, bestie, they're worth it 📚

🧚 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

...added to the global config section you're about to 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. cute little pid duo 💕

💀 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. periodt. 💅

---

⭐ 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@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.

---

okay and that's the whole page, bestie 🫶 this one shipped with perl v5.42.3, dated 2026-10-19 — so go forth, profile your mod_perl apps, and remember to rm those dbi.prof.* files when you're done. mwah 💜✨