[OOZIE-3160] PriorityDelayQueue put()/take() can cause significant CPU load due to busy waiting

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: trunk
• Fix Version/s: 5.1.0
• Component/s: core

Environment

all platforms

• Assignee: Peter Bacsko
• Reporter: jj
• Created: 14/Jan/18 07:58
• Updated: 18/Jan/19 09:02
• Resolved: 03/Oct/18 12:45

Description

oozie process always consume high cpu. in my mechine,around 10%.

I check the source code，find take() method in PriorityDelayQueue class。

code:

public QueueElement<E> take() throws InterruptedException {
    QueueElement<E> e = poll();
    while (e == null) {
        Thread.sleep(10);
        e = poll();
    }
    return e;
}

i think it's the reason of this problem. it's keep while, not await.

Issue Links

• blocks: OOZIE-3352 [tests] TestCallableQueueService#testPriorityExecutionOrder() is flaky
• blocks: OOZIE-3349 Test cases in oozie fail with java.net.ConnectException
• blocks: OOZIE-3229 [client] [ui] Improved SLA filtering options
• is related to: OOZIE-1855 TestPriorityDelayQueue#testPoll failed intermittently in Jenkins
• relates to: OOZIE-3349 Test cases in oozie fail with java.net.ConnectException
• relates to: OOZIE-3357 [core] More graceful CallableQueueService#destroy()
• links to: POC Review
• links to: ReviewBoard review request for amendment commits