APAR status
Closed as program error.
Error description
In WSAS 5.X, Upon Analyisis of the HeapDump we notice the number
of"com/ibm/ws/webcontainer/srt/WebAppInvoker" objects grow over
a period of time, The number is almost double the number
of the invocation cache setting.
Details : The default invocation cache setting is 50 for each
webcontainer thread and the deafult webcontainer thread pool is
50. so at any given point you should see no more than 2500
entries. but Analysis of Hepadumps, taken during Peak load
suggest that there are close to 5000 entires
One cache entry loosely equates to one
" com/ibm/ws/webcontainer/srt/WebAppInvoker" object
Here is the standard formula to calculate the cache entries
V 5.X
If the thread pool size is set to P and invocation cache size is
set to C, the total number of cached WebAppInvoker is
(2 * P + 1) * C
V 4.X
The total number is (P + 1) * C
In V5, it approximately doubled the number of cached objects
comparing to V4 or calculated number.
Reason for increase in V5.X:
The reason of the increase is that, in V5, the number of request
processors created by transport is (2 * P + 1) and each
processor has an invocation cache of up to C cached objects.
Local fix
no Work Around available at this time
Problem summary
****************************************************************
* USERS AFFECTED: WebSphere Application Servers version 5 *
* users whose application servers are under *
* a heavy load. *
****************************************************************
* PROBLEM DESCRIPTION: In WebSphere Application Server V5, *
* the number of cached webAppInvokers *
* almost doubled. The V5 design consumed *
* more memory the one in V4. *
* *
* In V5, the formula *
* cached objects = #threads * cache size *
* was not held. *
****************************************************************
* RECOMMENDATION: *
****************************************************************
The connection pool creates many waiting connections in V5.
Each of these connections is associated with an invocation
cache. This causes the large amount of invocation caches to
be created.
Problem conclusion
The invocation cache was detatched from the
SRPRequestProcessor. By changing this to be purely thread
based, the number of caches created will not exceed the
maximum number of threads.
The formula: "cached objects = #threads * cache size" holds
with this fix.
The fix for this APAR is currently targeted for inclusion in
fixpacks 5.0.2.12 and 5.1.1.6. Please refer to the recommended
updates page for delivery information:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
Temporary fix
ZE Fix Error
PK12027 2005/09/29
NOTE:
PK12027 ZE'd by
PK15035. Please see
PK15035
Comments
APAR information |
APAR number |
PK05682 |
Reported component name |
WAS NETWRK DEPL |
Reported component ID |
5630A3601 |
Reported release |
10A |
Status |
CLOSED PER |
PE |
NoPE |
HIPER |
NoHIPER |
Special Attention |
NoSpecatt |
Submitted date |
2005-05-12 |
Closed date |
2005-06-28 |
Last modified date |
2005-11-10 |
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
PK06649
Modules/Macros
Publications Referenced
|
Fix information |
Fixed component name |
WAS NETWRK DEPL |
Fixed component ID |
5630A3601 |
Applicable component levels |
R003 PSY |
UP |
R00A PSY |
UP |
R00H PSY |
UP |
R00I PSY |
UP |
R00P PSY |
UP |
R00S PSY |
UP |
R00W PSY |
UP |
R103 PSY |
UP |
R10A PSY |
UP |
R10H PSY |
UP |
R10I PSY |
UP |
R10P PSY |
UP |
R10S PSY |
UP |
R10W PSY |
UP |
|