PM43581: SLOW MEMORY LEAK OCCURS WHEN USING PMI REQUEST METRICS CONFIGURED IN "DEBUG" MODE

Fixes are available

APAR status

Closed as program error.

Error description

When WebSphere Application Server is configured in "DEBUG"
mode for Performance Monitoring Infrastructure (PMI) Request
Metrics and using Application Response Measurement (ARM) agents
causes a slow memory leak occurs.

Heapdump may show the following as leak suspect

394,031,304 (71%) [144] 12 array of java/util/HashMap$Entry
0x3fe20708
393,843,192 (71%) [32] 2 java/util/HashMap$Entry 0x3fe206e8
393,842,976 (71%) [72] 7
com/ibm/ws/runtime/component/ThreadPoolMgrImpl$ThreadPoolProxy
0x3fe206a0
393,841,992 (71%) [104] 5 com/ibm/ws/util/ThreadPool
0x3fe207a8
393,841,704 (71%) [48] 2 java/util/HashMap 0x3fe20810
393,841,640 (71%) [80] 1 array of java/util/HashMap$Entry
0x3fe20840
393,841,560 (71%) [32] 2 java/util/HashMap$Entry
0x3f03b040
393,841,528 (71%) [136] 11
com/ibm/ws/util/ThreadPool$Worker
0x3f03ade0
239,092,776 (43%) [72] 6 java/lang/ThreadGroup
0x392148a0
154,676,168 (28%) [232] 14 array of java/lang/Object
0x3f03b1a8
154,658,640 (28%) [136] 7
com/ibm/ws/pmi/reqmetrics/PmiRmThreadCtx 0x3f03b630
154,640,016 (28%) [32] 1
com/ibm/ws/pmi/reqmetrics/PmiRmCache
0x3f03b7f8
154,639,984 (28%) [24] 1 java/util/ArrayList
0x3f03b818
154,639,960 (28%) [1,191,488] 262,754 array of
java/lang/Object 0x4848c590      <==== Leak 154M (28%)

189,030,200 (34%) [32] 113 class
com/ibm/ws/pmi/reqmetrics/PmiReqMetricsImpl 0x31b2a9c0
189,025,384 (34%) [32] 44 class
com/ibm/ws/pmi/reqmetrics/WebAppReqMetricsListener 0x31b4f0e0
189,020,664 (34%) [48] 1 java/util/HashMap 0x3cb0e650
189,020,616 (34%) [272] 20 array of java/util/HashMap$Entry
0x3e5d39d0
156,038,696 (28%) [32] 2 java/util/HashMap$Entry 0x3e5d39b0
156,038,448 (28%) [248] 44
com/ibm/ws/wswebcontainer/webapp/WebApp
0x3e1e6268
143,289,560 (26%) [24] 1 java/util/ArrayList 0x3e1e6c80
143,289,536 (26%) [56] 1 array of java/lang/Object
0x3e1e6c98
143,289,480 (26%) [24] 2
org/apache/myfaces/orchestra/conversation/servlet/ConversationMa
nagerSes
sionListener 0x3e9a3c68
143,289,456 (26%) [112] 8
org/apache/myfaces/orchestra/conversation/ConversationWiperThrea
d
0x386b1678
143,289,120 (26%) [16] 1 java/util/HashSet 0x386b3960
143,289,104 (26%) [48] 2 java/util/HashMap 0x386b3970
143,289,040 (26%) [262,160] 4,096 array of
java/util/HashMap$Entry 0x47b2c590  <==== Leak 143M  (26%)

Local fix

use PERFORMANCE-DEBUG mode instead DEBUG mode

Problem summary

****************************************************************
* USERS AFFECTED:  All users of IBM WebSphere Application      *
*                  Server versions 6.1, 7.0, and 8.0           *
****************************************************************
* PROBLEM DESCRIPTION: When WebSphere Application Server is    *
*                      configured in "DEBUG" mode for          *
*                      Performance Monitoring Infrastructure   *
*                      (PMI) Request Metrics using ARM         *
*                      agents, OutOfMemory occurs which leads  *
*                      to JVM crash.                           *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
This is not seen for small number of requests, but as the
number of request keeps on increasing the number of
PmiRmCorrelator objects keeps growing and are not released.
This
ultimately leads to OutOfMemory and JVM crash.

Problem conclusion

This problem is fixed by making sure that PmiRMCorrelator
objects are reused from cache and a new one is only created
when the cache is empty. This avoids too many PmiRmCorrelator
objects getting created for every request at a component which
keeps the number of PMIRMCorrelator objects under control and
avoids the OutOfMemory and JVM Crash.

The fix for this APAR is currently targeted for inclusion in
fix packs 6.1.0.41, 7.0.0.21 and 8.0.0.2.  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
PM43581
Reported component name
WEBS APP SERV N
Reported component ID
5724H8800
Reported release
61I
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2011-07-12
Closed date
2011-08-12
Last modified date
2011-08-12

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
WEBS APP SERV N
Fixed component ID
5724H8800

Applicable component levels

R61A PSY
UP
R61H PSY
UP
R61I PSY
UP
R61P PSY
UP
R61S PSY
UP
R61W PSY
UP
R61Z PSY
UP
R700 PSY
UP
R800 PSY
UP

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSEQTP","label":"WebSphere Application Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"6.1","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
27 October 2021

Tips

PM43581: SLOW MEMORY LEAK OCCURS WHEN USING PMI REQUEST METRICS CONFIGURED IN "DEBUG" MODE

Fixes are available

Subscribe

APAR status

Closed as program error.

Error description

Local fix

Problem summary

Problem conclusion

Temporary fix

Comments

APAR Information

APAR number

Reported component name

Reported component ID

Reported release

Status

PE

HIPER

Special Attention

Submitted date

Closed date

Last modified date

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

Fixed component ID

Applicable component levels

R61A PSY

R61H PSY

R61I PSY

R61P PSY

R61S PSY

R61W PSY

R61Z PSY

R700 PSY

R800 PSY

Document Information

Share your feedback

Need support?