Fixes are available
16.0.0.2: WebSphere Application Server Liberty 16.0.0.2
16.0.0.3: WebSphere Application Server Liberty 16.0.0.3
16.0.0.4: WebSphere Application Server Liberty 16.0.0.4
17.0.0.1: WebSphere Application Server Liberty 17.0.0.1
17.0.0.2: WebSphere Application Server Liberty 17.0.0.2
17.0.0.3: WebSphere Application Server Liberty 17.0.0.3
17.0.0.4: WebSphere Application Server Liberty 17.0.0.4
18.0.0.1: WebSphere Application Server Liberty 18.0.0.1
18.0.0.2: WebSphere Application Server Liberty 18.0.0.2
18.0.0.3: WebSphere Application Server Liberty 18.0.0.3
18.0.0.4: WebSphere Application Server Liberty 18.0.0.4
19.0.0.1: WebSphere Application Server Liberty 19.0.0.1
19.0.0.2: WebSphere Application Server Liberty 19.0.0.2
19.0.0.3: WebSphere Application Server Liberty 19.0.0.3
19.0.0.4: WebSphere Application Server Liberty 19.0.0.4
19.0.0.5: WebSphere Application Server Liberty 19.0.0.5
19.0.0.6: WebSphere Application Server Liberty 19.0.0.6
19.0.0.7: WebSphere Application Server Liberty 19.0.0.7
19.0.0.8: WebSphere Application Server Liberty 19.0.0.8
19.0.0.9: WebSphere Application Server Liberty 19.0.0.9
19.0.0.10: WebSphere Application Server Liberty 19.0.0.10
19.0.0.11: WebSphere Application Server Liberty 19.0.0.11
19.0.0.12: WebSphere Application Server Liberty 19.0.0.12
20.0.0.1: WebSphere Application Server Liberty 20.0.0.1
20.0.0.2: WebSphere Application Server Liberty 20.0.0.2
20.0.0.3: WebSphere Application Server Liberty 20.0.0.3
20.0.0.4: WebSphere Application Server Liberty 20.0.0.4
20.0.0.5: WebSphere Application Server Liberty 20.0.0.5
20.0.0.6: WebSphere Application Server Liberty 20.0.0.6
20.0.0.7: WebSphere Application Server Liberty 20.0.0.7
20.0.0.8: WebSphere Application Server Liberty 20.0.0.8
20.0.0.9: WebSphere Application Server Liberty 20.0.0.9
20.0.0.10: WebSphere Application Server Liberty 20.0.0.10
20.0.0.11: WebSphere Application Server Liberty 20.0.0.11
20.0.0.12: WebSphere Application Server Liberty 20.0.0.12
21.0.0.3: WebSphere Application Server Liberty 21.0.0.3
21.0.0.4: WebSphere Application Server Liberty 21.0.0.4
21.0.0.5: WebSphere Application Server Liberty 21.0.0.5
21.0.0.6: WebSphere Application Server Liberty 21.0.0.6
21.0.0.7: WebSphere Application Server Liberty 21.0.0.7
21.0.0.8: WebSphere Application Server Liberty 21.0.0.8
21.0.0.9: WebSphere Application Server Liberty 21.0.0.9
21.0.0.1: WebSphere Application Server Liberty 21.0.0.1
21.0.0.2: WebSphere Application Server Liberty 21.0.0.2
21.0.0.10: WebSphere Application Server Liberty 21.0.0.10
21.0.0.11: WebSphere Application Server Liberty 21.0.0.11
21.0.0.12: WebSphere Application Server Liberty 21.0.0.12
22.0.0.1: WebSphere Application Server Liberty 22.0.0.1
22.0.0.2: WebSphere Application Server Liberty 22.0.0.2
22.0.0.3: WebSphere Application Server Liberty 22.0.0.3
22.0.0.4: WebSphere Application Server Liberty 22.0.0.4
APAR status
Closed as program error.
Error description
The WebSphere Liberty transaction manager creates its own Executor thread pool during application startup. These threads are used for tasks like timing out hung transactions, etc. Since these threads are created lazily (that is, not until an application actually needs to use transactions), the thread that creates these threads will have an application's classloader set as its context classloader. That classloader will then be set as the context classloader for the newly created transaction threads. When that application is stopped, the application's classloader should be able to be garbage collected, but the garbage collector is prevented from collecting this classloader because the transaction threads still have a strong reference to it.
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All users of IBM WebSphere Application * * Server Liberty * **************************************************************** * PROBLEM DESCRIPTION: Application classloaders are leaked by * * transaction monitoring threads. * **************************************************************** * RECOMMENDATION: * **************************************************************** The WebSphere Liberty transaction manager creates its own Executor thread pool during application startup. These threads are used for tasks like timing out hung transactions, etc. Since these threads are created lazily (i.e. not until an application actually needs to use transactions), the thread that creates these threads will have an application's classloader set as its context classloader. That classloader will then be set as the context classloader for the newly created transaction threads. When that application is stopped, the application's classloader should be able to be garbage collected, but the garbage collector is prevented from collecting this classloader because the transaction threads still have a strong reference to it.
Problem conclusion
The fix for this APAR is to ensure that newly created transaction threads do not reference the application's classloader, thus preventing the leak. The fix for this APAR is currently targeted for inclusion in fix pack 16.0.0.2. Please refer to the Recommended Updates page for delivery information: http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
Temporary fix
Comments
APAR Information
APAR number
PI61468
Reported component name
WAS LIBERTY COR
Reported component ID
5725L2900
Reported release
855
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2016-04-26
Closed date
2016-05-04
Last modified date
2016-06-22
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
WAS LIBERTY COR
Fixed component ID
5725L2900
Applicable component levels
R855 PSY
UP
Document Information
Modified date:
04 May 2022