Triage for Bugzilla¶
All teams working on Firefox using either or both Mozilla-central and Bugzilla are expected to follow the following process.
What is a Triaged Bug¶
The new definition of Triaged will be Firefox-related bugs of type
defect where the component is not
UNTRIAGED, and a severity value not equal to
Bugs of type Task or Enhancement may have a severity of
but defects must have a severity that is neither
We want to make sure that we looked at every defect and a severity has been defined. This way, we make sure that we did not miss any critical issues during the development and stabilization cycles.
Staying on top of the bugs in your component means:
You get ahead of critical regressions and crashes which could trigger a point release if uncaught
And you don’t want to spend your holiday with the Release Management team (not that they don’t like you)
Your bug queue is not overwhelming
Members of your team do not see the bug queue and get the ‘wiggins’
Engineering managers and directors are responsible for naming the individuals responsible for triaging all types of bugs in a component.
We use Bugzilla to manage this. See the list of triage owners.
If you need to change who is responsible for triaging a bug in a component, please file a bug against bugzilla.mozilla.org in the Administration component. When a new component is created, a triage owner must be named.
Some components are monitored by a rotation of triagers. In those cases, the triage owner on Bugzilla will be automatically updated to reflect the person on the rotation. The rotations are managed as calendars.
If you wish to set up a rotation for triaging one or more components, add a link to your rotation calendar in the triage rotations spreadsheet.
Firefox::General and Toolkit::General¶
Bugs in Firefox::General are fitted with Bug Bug’s model to see if there’s another component with a high liklihood of fit, and if a threshold confidence is achieved, the bug is moved to that component.
Members of the community also review bugs in this component and try to move them.
What Do You Triage¶
As a triage owner the queries you should be following for your component are:
All open bugs, in your components without a pending
needinfoflag which do not have a valid value of severity set
All bugs with active review requests in your component which have not been modified in five days
All bugs with reviewed, but unlanded patches in your components
All bugs with a needinfo request unanswered for more than 10 days
There’s a tool with these queries to help you find bugs https://mozilla.github.io/triage-center/ and the source is at https://github.com/mozilla/triage-center/.
If a bug is an enhancement it needs a priority set and a target release or program milestone. These bugs are normally reviewed by product managers. Enhancements can lead to release notes and QA needed that we also need to know about
If a bug is a task resulting in a changeset, release managers will need to known when this work will be done. A task such as refactoring fragile code can be risky.
Weekly or More Frequently (depending on the component) find un-triaged bugs in the components you triage.
Decide the Severity for each untriaged bug (you can override what’s already been set.)
These bugs are reviewed in the weekly Regression Triage meeting
Bugs of type
Bugs of type
regressionkeyword without a regression range
Automatic Bug Updates¶
When a bug is tracked for a release, i.e. the
flag is set to
blocking triage decisions will be overridden,
or made as follows:
If a bug is tracked for or blocking beta, release or ESR, its priority will be set to
If a bug is tracked for or blocking nightly, its priority will be set to
Because bugs can be bumped in priority it’s essential that triage owners review their P1 and P2 bugs frequently.
If a bug’s release status in Firefox version N was
its Severity is
S4 and its Priority is
P3 or lower (backlog,)
then its release status in Firefox version N+1, if the bug is still open,
is considered to be
Questions and Edge Cases¶
This bug is a feature request¶
Set the bug’s type to
enhancement, add the
feature keyword if
relevant, and state to
NEW. Set the bug’s Severity to
bug will be excluded from future triage queries.
This bug is a task, not a defect¶
Set the bug’s type to
task, and state to
NEW. Set the bug’s
N/A. This bug will be excluded from future triage queries.
If you are not sure of a bug’s type, check our rules for bug types.
This bug’s state is
Are there steps to reproduce? If not, needinfo the person who filed the
bug, requesting steps to reproduce. You are not obligated to wait
forever for a response, and bugs for which open requests for information
go unanswered can be
I need help reproducing the bug¶
Set a needinfo for the QA managers, Softvision project managers, or the QA owner of the component of the bug.
I don’t have enough information to make a decision¶
If you don’t have a reproduction or confirmation, or have questions
about how to proceed,
needinfo the person who filed the bug, or
someone who can answer.
The extreme case of not-enough-information is one which cannot be
answered with a
needinfo request. The reporter has shared all they
know about the bug, we are out of strategies to take to resolve it, but
the bug should be kept open.
Mark the bug as stalled by adding the
stalled keyword to it. The
keyword will remove it from the list of bugs to be triaged.
If a patch lands on a
stalled bug, automation will remove the
keyword. Otherwise, when the
keyword is removed, the bug will have
its priority reset to
-- and the components triage owner notified by
Bugs which remain
stalled for long periods of time should be
reviewed, and closed if necessary.
Bug is in the wrong Component¶
If the bug has a Severity of
N/A move the what
you think is the correct component, or needinfo the person
responsible for the component to ask them.
If the bug has a Severity of
S2 then notify Release Management
and contact the triage owner of the component for which you think it belongs to.
We cannot lose track of a high severity bug because it is in the wrong component.
My project is on GitHub¶
We have a guide for GitHub projects to follow when triaging. (Note: this guide needs updating.)
Multiple times weekly¶
Use queries for the components you are responsible for in https://mozilla.github.io/triage-center/ to find bugs in need of triage.
For each untriaged bug:
Assign a Severity
Do not assign a
defecta Severity of
You can, but are not required to set the bug’s Priority.
Watch open needinfo flags¶
Don’t let open needinfo flags linger for more than two weeks.
Close minor bugs with unresponded needinfo flags.
Follow up on needinfo flag requests.
The Triage Center tool will help you find these.
End of Iteration/Release Cycle¶
S2 bugs at the end of the release cycle
will require review by engineering and release management. A
policy on this is forthcoming.
(The guidelines on bug priority are under review.)
Are there open P1s? Revisit their priority,
and move to them to the backlog (
P2 bugs that should move to
for the next cycle?
P2 you now know are lower priority,
P3 bugs you now know you won’t get to?
Either demote to
P5 (will accept patch) or
Ask in #bug-handling on chat.mozilla.org