APAR status
Closed as program error.
Error description
cache size is "2" (only 2 entries can be cached)
visit page 1 (we do a "put" to the cache for page 1)
visit page 2 (we do a "put" to the cache for page 2) ... the
cache is now full
visit page 1 (we have a "hit" when we do a "get" from the cache)
visit page 3 ... cache is full, so we need to replace an
existing entry
Our understanding is that the dynacache performs, by default,
a LRU analaysis when the cache is full, in order to "put" new
entries in the cache. In this example, when we visit page 3,
the cache is full. We expect "page 2" to be removed from the
cache, since we most recently visited page 1, and it was found
in the cache (via a "get"). However, page 1 (which was the
first page to enter the cache) is removed to make room for
page 3.
Local fix Problem summary
****************************************************************
* USERS AFFECTED: All dynamic cache users *
****************************************************************
* PROBLEM DESCRIPTION: The Least Recently Used (LRU) function *
* of the dynamic cache is not working *
* properly *
****************************************************************
* RECOMMENDATION: *
****************************************************************
Dynamic cache does LRU analysis to make room for a new entry
when cache is full. Dynamic cache sometimes seems to remove
the most recently used entry instead of the least recently used.
Problem conclusion
This fix makes sure that it is always the least recently used
entry that is evicted when cache is full.
Temporary fix Comments
APAR information |
APAR number |
PQ84238 |
Reported component name |
WAS BASE 5.0 |
Reported component ID |
5630A3600 |
Reported release |
00W |
Status |
CLOSED PER |
PE |
NoPE |
HIPER |
NoHIPER |
Special Attention |
NoSpecatt |
Submitted date |
2004-02-05 |
Closed date |
2004-04-26 |
Last modified date |
2004-04-26 |
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Modules/Macros
Publications Referenced
Applicable component levels |
R003 PSY |
UP |
R00A PSY |
UP |
R00H PSY |
UP |
R00I PSY |
UP |
R00P PSY |
UP |
R00S PSY |
UP |
R00W PSY |
UP |
|