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https://issues.apache.org/jira/browse/OOZIE-3646?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Junfan Zhang updated OOZIE-3646:
--------------------------------
Description:
The limited thread execution mechanism aims to solve the dead-lock when all
active threads are executing the SignalXCommand's invokeAll method.
h2. Dead-lock when to happen
Assuming that Oozie CallableQueue thread pool size is 120, when all threads are
executing the {{SignalXCommand.startForkedActions}} method, a deadlock occurs.
Because in {{SignalXCommand.startForkedActions}}, the code of
{code:java}
List<Future<ActionExecutorContext>> futures =
Services.get().get(CallableQueueService.class)
.invokeAll(tasks);
{code}
will be sync executed, however now all callableQueue threads are busy.
h2. Solution
1. Need to limit directly invokeAll call when the num of rest threads is less
than the tasks
2. To obtain correct active threads number in callableQueue, the
SignalXCommand.class lock is needed.
was:
The limited thread execution mechanism aims to solve the dead-lock when all
active threads are executing the SignalXCommand's invokeAll method.
h2. Dead-lock when to happen
Assuming that Oozie CallableQueue thread pool size is 120, when all threads are
executing the {{SignalXCommand.startForkedActions}} method, a deadlock occurs.
Because in {{SignalXCommand.startForkedActions}}, the code of
{{List<Future<ActionExecutorContext>> futures =
Services.get().get(CallableQueueService.class)
.invokeAll(tasks);}} will be sync executed, however now all
callableQueue threads are busy.
h2. Solution
1. Need to limit directly invokeAll call when the num of rest threads is less
than the tasks
2. To obtain correct active threads number in callableQueue, the
SignalXCommand.class lock is needed.
> Possible dead-lock in SignalXCommand
> ------------------------------------
>
> Key: OOZIE-3646
> URL: https://issues.apache.org/jira/browse/OOZIE-3646
> Project: Oozie
> Issue Type: Bug
> Reporter: Junfan Zhang
> Assignee: Junfan Zhang
> Priority: Major
> Attachments: a1.png
>
>
> The limited thread execution mechanism aims to solve the dead-lock when all
> active threads are executing the SignalXCommand's invokeAll method.
> h2. Dead-lock when to happen
> Assuming that Oozie CallableQueue thread pool size is 120, when all threads
> are executing the {{SignalXCommand.startForkedActions}} method, a deadlock
> occurs.
> Because in {{SignalXCommand.startForkedActions}}, the code of
> {code:java}
> List<Future<ActionExecutorContext>> futures =
> Services.get().get(CallableQueueService.class)
> .invokeAll(tasks);
> {code}
> will be sync executed, however now all callableQueue threads are busy.
> h2. Solution
> 1. Need to limit directly invokeAll call when the num of rest threads is less
> than the tasks
> 2. To obtain correct active threads number in callableQueue, the
> SignalXCommand.class lock is needed.
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