xhprof Profiling¶
DDEV has built-in support for xhprof. The official PECL xhprof extension only supports PHP >=7.x.
Basic xhprof Usage¶
- Enable xhprof with
ddev xhprof on
(orddev xhprof
orddev xhprof enable
) and check its status withddev xhprof status
. ddev xhprof on
will show you the URL you can use to see the xhprof analysis,https://<projectname>.ddev.site/xhprof
shows recent runs. (It’s often useful to keep a tab or window open with this URL and refresh as needed.)- Use a web browser or other technique to visit a page whose performance you want to study. To eliminate first-time cache-building issues, you may want to hit it twice.
- Visit one of the links provided by
ddev xhprof on
and study the results. - On the profiler output page, you can drill down to the function that you want to study, or use the graphical “View Full Callgraph” link. Click the column headers to sort by number of runs and inclusive or exclusive wall time, then drill down into the function you want to study and do the same.
- The runs are erased on
ddev restart
. - If you’re using Apache with a custom
.ddev/apache/apache-site.conf
, you’ll need to make sure it includesAlias "/xhprof" "/var/xhprof/xhprof_html"
from DDEV’s default apache-site.conf.
For a tutorial on how to study the various xhprof reports, see the section “How to use XHPROF UI” in A Guide to Profiling with XHPROF. It takes a little time to get your eyes used to the reporting. (You don’t need to do any of the installation described in that article!)
Advanced xhprof Configuration¶
You can change the contents of the xhprof_prepend
function in .ddev/xhprof/xhprof_prepend.php
.
For example, you may want to add a link to the profile run to the bottom of the profiled web page. The provided xhprof_prepend.php
has comments and a sample function to do that, which works with Drupal 7. If you change it, remove the #ddev-generated
line from the top, and check it in (git add -f .ddev/xhprof/xhprof_prepend.php
).
Another example: you could exclude memory profiling so there are fewer columns to study. Change xhprof_enable(XHPROF_FLAGS_MEMORY);
to xhprof_enable();
in .ddev/xhprof/xhprof_prepend.php
and remove the #ddev-generated
at the top of the file. See the docs on xhprof_enable().