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Why EventDispatcher is blocked

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In our application, I am seeing below stack trace when doing performance test. The HTTP call /content/myproduct.product-details.json is executed multiple times.

 

"10.43.0.54 [1622796489658] GET /content/myproduct.product-details.json HTTP/1.1" #38568 
prio=5 os_prio=0 cpu=1873.84ms elapsed=520.13s tid=0x00007f9d40ec3800 nid=0xe20 waiting 
for monitor entry  [0x00007f9d10dd7000]
 java.lang.Thread.State: BLOCKED (on object monitor)
at org.apache.felix.framework.EventDispatcher.updateListener(EventDispatcher.java:397)
- waiting to lock <0x00000007143ec440> (a org.apache.felix.framework.EventDispatcher)
at org.apache.felix.framework.EventDispatcher.addListener(EventDispatcher.java:183)
at org.apache.felix.framework.Felix.addServiceListener(Felix.java:3615)
at org.apache.felix.framework.BundleContextImpl.addServiceListener(BundleContextImpl.java:259)
at org.osgi.util.tracker.ServiceTracker.open(ServiceTracker.java:297)
- locked <0x00000007bce37348> (a org.osgi.util.tracker.ServiceTracker$Tracked)
- locked <0x00000007bce372a8> (a org.osgi.util.tracker.ServiceTracker)
at org.osgi.util.tracker.ServiceTracker.open(ServiceTracker.java:264)
at org.apache.jackrabbit.oak.osgi.OsgiWhiteboard.track(OsgiWhiteboard.java:160)
at org.apache.jackrabbit.oak.osgi.OsgiWhiteboard.track(OsgiWhiteboard.java:112)
at org.apache.jackrabbit.oak.osgi.OsgiWhiteboard.track(OsgiWhiteboard.java:107)
at org.apache.jackrabbit.oak.spi.whiteboard.WhiteboardUtils.getService(WhiteboardUtils.java:197)
at org.apache.jackrabbit.oak.spi.whiteboard.WhiteboardUtils.getService(WhiteboardUtils.java:145)
at org.apache.jackrabbit.oak.security.user.UserConfigurationImpl.getBlobAccessProvider(UserConfigurationImpl.java:276)
at org.apache.jackrabbit.oak.security.user.UserConfigurationImpl.getUserManager(UserConfigurationImpl.java:251)
at org.apache.jackrabbit.oak.security.authentication.token.TokenProviderImpl. (TokenProviderImpl.java:138)
at org.apache.jackrabbit.oak.security.authentication.token.TokenConfigurationImpl.getTokenProvider(TokenConfigurationImpl.java:162)
at org.apache.jackrabbit.oak.spi.security.authentication.token.CompositeTokenConfiguration$1.apply(CompositeTokenConfiguration.java:46)
at org.apache.jackrabbit.oak.spi.security.authentication.token.CompositeTokenConfiguration$1.apply(CompositeTokenConfiguration.java:43)

 

 

The servlet (/content/myproduct.product-details.json) is trying to get product details by creating a service resource resolver object on each request. As per my understanding, every time when I get service resource resolver object then a resource resolver thread is executed and during this process OSGI container needs to know how to communicate with different bundles as per whiteboard pattern. And because of this HTTP thread is waitig to lock org.apache.felix.framework.EventDispatcher object.

Could you please let me know whether my understanding is correct or not? And why HTTP thread is not able to accquire the lock on the EventDispatcher object?

 

 

 

 

1 Accepted Solution

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Correct answer by
Community Advisor

 

Regularly capture thread dumps during performance issues to analyze and identify which threads are holding the locks and for how long. This can help pinpoint the source of contention.

 

Also, please assure that the sessions are short-lived and they are not competing for a common resource

 

 

 

 


Aanchal Sikka

View solution in original post

1 Reply

Avatar

Correct answer by
Community Advisor

 

Regularly capture thread dumps during performance issues to analyze and identify which threads are holding the locks and for how long. This can help pinpoint the source of contention.

 

Also, please assure that the sessions are short-lived and they are not competing for a common resource

 

 

 

 


Aanchal Sikka