1220113 - Evaluate asserting once in case of unclean shutdown

Status: RESOLVED WORKSFORME

(Toolkit :: Storage, defect)

Description

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

currently the only thing we do is firing a bunch of warnings about unfinalized statements, but that gets unnoticed until someone actually complains in a bug.

We may assert too.
The risk is:
1. increase random failures
2. annoy developers

we can control 1, we can do multiple Try runs with the assertion and check how we are.
2 should then happen rarely, since we have a bunch of tests, and in some cases it will be a positive thing (especially for add-on developers to properly shutdown their connections).

I'd start with 1, and see how bad is the impact, that should give us an idea of how much we may hit the assertion in the wild.

Comment 1

[Andrew Sutherland [:asuth] (he/him)]

Does assert in this case mean crash/abort in:
A) Debug builds / test builds only?
B) Dev edition / nightly builds only?
C) All production builds.

If we're talking 'C', then it seems likely that there are extensions out there that could make this shoot to the top of crash-stats and really frustrate some users.

If a goal is to keep the in-tree consumers clean, then "A" seems good enough for that.

If a goal is to find out about mis-use of mozStorage/SQLite.jsm by extensions in the field, then maybe telemetry or the Firefox Health Report mechanism is a better use-case since that can happen without crashing?  The only trick there might be that the finalization warnings would likely happen at shutdown which might be too late to report such things.  (But maybe those mechanisms thought of that and have helpers?)

Comment 2

[David Teller [:Yoric] - still alive but not very active]

I don't know of any helper, but a few mechanisms that collect their data too late write it to disk, to be able to submit it to Telemetry on the next launch.

Comment 3

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

In the last years we added MOZ_ASSERTS to shutdown, also thanks to add-ons not being able anymore to hook directly into Storage. So this is likely wfm.