904250 - [graph server] Performance monitoring should email patch authors who cause perf improvements

Status: RESOLVED FIXED

(Release Engineering :: General, defect)

Description

[Matt Brubeck (:mbrubeck)]

Attachment: patch

The graph server analysis script uses these rules for sending email (see bug 752002 for details):

Regressions:
* If there are up to five authors in the regression range, email dev-tree-management and each of the patch authors.
* If there are more than five authors, just email dev-tree-management.

Improvements:
* Just email dev-tree-management.

This patch leaves the rules unchanged for regressions.  It changes the rules for improvements to match the rules for regressions.  In other words, the new rules after this patch are:

Regressions and improvements:
* If there are up to five authors in the regression range, email dev-tree-management and each of the patch authors.
* If there are more than five authors, just email dev-tree-management.

I spoke to several other developers (including open polls on IRC and other places), and most were in favor of this change.  (Those who don't want the extra emails can filter them out if there are enough to warrant it.)  Reasons this is useful:

- When you are expecting a patch to affect performance, the email is useful confirmation.  Receiving it directly saves you the work of searching through the mailing list archives or manually inspecting graphs.

- When you're not expecting a performance improvement, it may be important to know that one has happened so you can figure out why.  (Sometimes it's a sign of a bug, for example if you accidentally disabled some code.)

- Warm fuzzy feeling for developers who write perf wins!

Comment 1

[Matt Brubeck (:mbrubeck)]

Attachment: patch

The previous patch touched the wrong line.  (state == 'regression' is true for both performance increases and decreases; isImprovement is what distinguishes the former from the latter.)

Comment 2

[Matt Brubeck (:mbrubeck)]

I posted to dev-platform to see if there are any objections to this change:
https://groups.google.com/d/topic/mozilla.dev.platform/jqMS41nc5Us/discussion

Comment 3

[Matt Brubeck (:mbrubeck)]

http://hg.mozilla.org/graphs/rev/7a1ba5f96bb8