Session scoped JSF beans accumulate in WebInjectionContainer when a distributable session cache is used

Environment

• JBoss Enterprise Application Platform (EAP) 7.x

Issue

• When our application has the <distributable/> tag in its WEB-INF/web.xml, we see heap growth from JSF session scoped beans accumulating in the WebInjectionContainer:

Class Name                                                                                             | Ref. Objects | Shallow Heap | Ref. Shallow Heap | Retained Heap
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service org.wildfly.extension.undertow.deployment.UndertowDeploymentService @ 0x50f329230              |      125,147 |           40 |         9,010,584 |            40
'- webInjectionContainer org.jboss.as.web.common.WebInjectionContainer @ 0x50f329298                   |      125,147 |           24 |         9,010,584 | 3,401,632,128
   '- instanceMap org.jboss.as.web.common.ConcurrentReferenceHashMap @ 0x50f3292b0                     |      125,147 |           48 |         9,010,584 | 3,401,632,104
      '- segments org.jboss.as.web.common.ConcurrentReferenceHashMap$Segment[2] @ 0x50f3292e0          |      125,147 |           24 |         9,010,584 | 3,401,632,056
         |- [0] org.jboss.as.web.common.ConcurrentReferenceHashMap$Segment @ 0x50f34b958               |       62,788 |           56 |         4,520,736 | 1,502,618,200
         |  '- table org.jboss.as.web.common.ConcurrentReferenceHashMap$HashEntry[131072] @ 0x591400000|       62,788 |      524,304 |         4,520,736 | 1,502,618,032
         |     |- [58249] org.jboss.as.web.common.ConcurrentReferenceHashMap$HashEntry @ 0x641530970   |            5 |           32 |               360 |         8,144
         |     |  |  |- keyRef com.redhat.BeanInstance @ 0x641530990               |            1 |           72 |                72 |         1,328
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------

• Session attribute listeners are invoked upon session destruction with a non-distributable session manager, but they are no longer invoked in this case when our app is set for <distributable/>

Resolution

• Upgrade to 7.2.9 or 7.3.2 for some relevant fixes and to 7.3.8+ or 7.4.2+ for remaining fixes related to session timeout events causing a leak if triggered on a cluster member different from the member last serving the session and its requests.
• As a workaround, disable the <distributable/> flag

Root Cause

• The distributable session manager does not truly remove session attributes upon session destruction while non-distributable session manager does. Thus, JSF session beans are not destroyed since com.sun.faces.application.WebappLifecycleListener is not invoked
  • This content is not included.WFLY-13616
    • This content is not included.JBEAP-19744
    • This content is not included.JBEAP-19745
• The JSF bean instances were originally cached separately from the session itself. This could lead to a scenario in a cluster where the session times out on one member and doesn't trigger removal of the JSF bean on another member
  • This content is not included.WFLY-14698
    • This content is not included.This content is not included.https://issues.redhat.com/browse/JBEAP-21498
    • This content is not included.This content is not included.https://issues.redhat.com/browse/JBEAP-21536

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