-Werror interacts poorly with "Memory constraints are impeding performance; please increase max heap size"

[kennknowles]

My apologies if this is a duplicate report. I recall discussing it before but have failed to find the prior issue or mailing list thread.

We use -Werror for code hygiene, to give careful control over what warnings we allow and which we do not.

Checkerframework sometimes issues a warning "Memory constraints are impeding performance; please increase max heap size." which is upgraded to an error and causes the build to fail.

It is not desirable, from my point of view, for this warning to have the same effect on a build as an illegal use of rawtypes, etc.

The issue apache/beam#20819 tracks this now (migrated from https://issues.apache.org/jira/browse/BEAM-11837 which has additional context). In the past we have fixed this by giving more memory. But realistically we would prefer to have the build succeed even if it is slow for a bit.

Some ideas:

• a flag to downgrade it to an INFO log (it is still good to have the info in case one is debugging a super slow build)
• increase the amount of GC thrashing needed to issue the warning
• some combination of the two, where the INFO log becomes a WARNING log after some number of occurrences