See for example https://integration.wikimedia.org/ci/job/mediawiki-extensions-hhvm-jessie/5115/console. The tests seem to complete, but then the log reports a segfault and Jenkins marks the job as failed.
```
16:13:38 Time: 5.28 minutes, Memory: 763.68MB
16:13:38
16:13:38 OK, but incomplete, skipped, or risky tests!
16:13:38 Tests: 14107, Assertions: 116135, Skipped: 119, Risky: 1.
16:13:41 [Wed Feb 1 16:13:41 2017] [hphp] [2312:7f1f075ca6c0:0:000002] [] Lost parent, LightProcess exiting
16:13:41 [Wed Feb 1 16:13:41 2017] [hphp] [2311:7f1f075ca6c0:0:000002] [] Lost parent, LightProcess exiting
16:13:41 [Wed Feb 1 16:13:41 2017] [hphp] [2310:7f1f075ca6c0:0:000002] [] Lost parent, LightProcess exiting
16:13:41 [Wed Feb 1 16:13:41 2017] [hphp] [2309:7f1f075ca6c0:0:000002] [] Lost parent, LightProcess exiting
16:13:41 [Wed Feb 1 16:13:41 2017] [hphp] [2308:7f1f075ca6c0:0:000002] [] Lost parent, LightProcess exiting
16:13:43 /srv/deployment/integration/slave-scripts/bin/mw-run-phpunit-allexts.sh: line 23: 2306 Segmentation fault (core dumped) php -dzend.enable_gc=0 phpunit.php --log-junit "$JUNIT_DEST" --testsuite extensions
16:13:43 Build step 'Execute shell' marked build as failure
16:13:43 Recording test results
16:13:48 Archiving artifacts
16:13:51 [PostBuildScript] - Execution post build scripts.
16:13:51 [PostBuildScript] Build is not success : do not execute script
16:13:51 Finished: FAILURE
```
This also seems to be affecting mediawiki-phpunit-hhvm-jessie, see for example https://integration.wikimedia.org/ci/job/mediawiki-phpunit-hhvm-jessie/2859/console.
---
Last working builds were shortly before 15:00 UTC.
```
14:12 <moritzm> uploaded hhvm 3.12.12 to carbon
```
Nodepool start refreshing the images at 14:14UTC which takes roughly 10 minutes. Once complete, newly created instances use that new image.