NSS has increased the security of Master Password's key derivation function to modern levels, dramatically increasing the compute complexity around master password.

For TaskCluster builds that's unnecessary, and leads to spurious timeouts.

It's controllable via an environment variable NSS_MAX_MP_PBE_ITERATION_COUNT which we've set to 100 for NSS. We should set the same for all TaskCluster tests.

Unfortunately this is blocking NSS' uplift, so marking as a blocker. The NSS team can start producing a patch for TC.

It's not clear to me where to do the insert, but here's a stab-in-the-dark try push:
https://treeherder.mozilla.org/#/jobs?repo=try&revision=760d2121ab233028dcc7e8637bcc4e91a87c95b2

Bugbug thinks this bug is a defect, but please change it back in case of error.

This will only apply to tests in CI and not locally, is that the intended behaviour?

Mmm. I'm not sure where to set it for, say. all tests. I guess one could add it to the relevant mochitest.ini and browser.ini files, but it should probably be global so we don't have to play intermittent-whack-a-mole.

Suggestions?

Try this function:
https://searchfox.org/mozilla-central/source/testing/mozbase/mozrunner/mozrunner/utils.py#87

It should catch mochitests, reftest and web-platform-tests (and variants). If you need this for e.g xpcshell, cppunittest or other smaller harnesses you might need to also copy it to those harnesses. Let me know if you need a hand finding it all.

Thanks, :ahal. Updated, and try-run running: https://treeherder.mozilla.org/#/jobs?repo=try&revision=5dd009a15c213a9d84af6a65842fa96e44931c96

https://hg.mozilla.org/mozilla-central/rev/50eb05e09687