[HBASE-23779] Up the default fork count to make builds complete faster; make count relative to CPU count

• Type: Task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha-1, 2.3.0
• Component/s: test
• Hadoop Flags: Reviewed

Release Note

Pass --threads=2 building on jenkins. It shortens nightly build times by about ~25%.

It works by running module build/test in parallel when dependencies allow. Upping the forkcount beyond the pom default of 0.25C would have us broach our CPU budget on jenkins when two modules are running in parallel (2 modules at 0.25% of CPU each makes 0.5C and on jenkins, hadoop nodes run two jenkins executors per host). Higher forkcounts also seems to threaten build stability.

For running tests locally, to go faster, up fork count.

$ x="0.5C" ; mvn --threads=2 -Dsurefire.firstPartForkCount=$x -Dsurefire.secondPartForkCount=$x test -PrunAllTests

You could up the x from 0.5C to 1.0C but YMMV (On overcommitted hardware, tests start bombing out pretty soon after startup). You could try upping thread count but on occasion are likely to overcommit hardware.

• Assignee: Michael Stack
• Reporter: Michael Stack
• Created: 31/Jan/20 00:39
• Updated: 13/Apr/20 23:33
• Resolved: 13/Apr/20 23:29

Description

Tests take a long time. Our fork count running all tests are conservative – 1 (small) for first part and 5 for second part (medium and large). Rather than hardcoding we should set the fork count to be relative to machine size. Suggestion here is 0.75C where C is CPU count. This ups the CPU use on my box.

Looking up at jenkins, it seems like the boxes are 24 cores... at least going by my random survey. The load reported on a few seems low though this not representative (looking at machine/uptime).

More parallelism willl probably mean more test failure. Let me take a look see.

Issue Links

• breaks: HBASE-23923 Set suitable forkCount when running pre commit
• is related to: HBASE-23783 Address tests writing and reading SSL/Security files in a common location.
• is related to: HBASE-23795 Enable all tests to be run in parallel on reused JVMs.
• is related to: HBASE-24072 Nightlies reporting OutOfMemoryError: unable to create new native thread
• relates to: YETUS-934 Precommit does not accept a caller's value of MAVEN_ARGS
• links to: GitHub Pull Request #1108
• links to: GitHub Pull Request #1461