Do not use synchronised checks during event processing #363
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Using synchronised checks during event processing leads to contention on GerritWorker threads. Especially if lock is done on ToGerritRunListener. So, to speed up the processing we need to get rid of `isProjectTriggeredAndIncomplete`. `isProjectTriggeredAndIncomplete` can be replaced by `isTriggered` and `isBuilding`. That transforms the previos version of check to `(isTriggered && isBuilding) || isTriggered`. So, it's absolutely safe to keep `isTriggered` only. After that plugin itself does not use `isProjectTriggeredAndIncomplete`.
Skaiol
approved these changes
May 16, 2018
Parallel triggering of multiple jobs for the same event should not produce any issues as there is synchronization in onStarted method as well. But in same time onTriggered also is part of initial event processing. That's why it's important to not have a lock here.
Jimilian
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rsandell
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Jul 10, 2018
| //TODO stop builds for earlier patch-sets on same change. | ||
| memory.triggered(event, project); | ||
| if (event instanceof GerritEventLifecycle) { | ||
| ((GerritEventLifecycle)event).fireProjectTriggered(project); | ||
| } | ||
| //Logging | ||
| String name = null; |
| @@ -328,18 +332,13 @@ protected void cleanUpGerritCauses(GerritCause firstFound, Run build) { | |||
| * @param project the project that will be built. | |||
| * @param event the event that caused the build to be scheduled. | |||
| */ | |||
| public synchronized void onTriggered(Job project, GerritTriggeredEvent event) { | |||
| public void onTriggered(Job project, GerritTriggeredEvent event) { | |||
| //TODO stop builds for earlier patch-sets on same change. | |||
| memory.triggered(event, project); | |||
| if (event instanceof GerritEventLifecycle) { | |||
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This is a change that might have outside repercussions. The lifecycle listeners might have assumptions about owning the monitor when called (which is normal behavior in most listener cases that I've seen)
But I think I can live with that risk if this change is really needed.
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Using synchronised checks during event processing leads to contention on
GerritWorker threads. Especially if lock is done on ToGerritRunListener.
So, to speed up the processing we need to get rid of
isProjectTriggeredAndIncomplete.isProjectTriggeredAndIncompletecan be replaced byisTriggeredandisBuilding.That transforms the previos version of check to
(isTriggered && isBuilding) || isTriggered.So, it's absolutely safe to keep
isTriggeredonly.After that plugin itself does not use
isProjectTriggeredAndIncomplete.Screenshot that shows that we were waiting for 2 minutes to parse 4 events.
