APAR status
Closed as program error.
Error description
Error Message: Unnecessary compactions happens with "failed to expand" reason for percolate collect. Here is an example: <gc-op id="27717" type="scavenge" timems="261.868" contextid="27714" timestamp="2013-08-09T16:11:27.582"> <scavenger-info tenureage="14" tiltratio="85" /> <memory-copied type="nursery" objects="4782292" bytes="248767008" bytesdiscarded="265680" /> <memory-copied type="tenure" objects="211023" bytes="12994312" bytesdiscarded="131992" /> <copy-failed type="tenure" objects="4" bytes="737312" /> <finalization candidates="49" enqueued="47" /> <ownableSynchronizers candidates="206" cleared="174" /> <references type="phantom" candidates="1" cleared="0" enqueued="0" /> </gc-op> .... <af-start id="27735" totalBytesRequested="80" timestamp="2013-08-09T16:11:31.892" intervalms="4572.591" /> <percolate-collect id="27736" from="nursery" to="global" reason="Previous scavenge failed to expand" timestamp="2013-08-09T16:11:31.892"/> <gc-start id="27737" type="global" contextid="27726" timestamp="2013-08-09T16:11:31.892"> .... <gc-op id="27746" type="compact" timems="5445.129" contextid="27726" timestamp="2013-08-09T16:11:37.704"> <compact-info movecount="55137760" movebytes="2048168416" reason="compact on aggressive collection" /> </gc-op> . Stack Trace: N/A .
Local fix
Problem summary
This compact reason "failed to expand" should be aggressive only if a subsequent scavenge leads to another percolate.
Problem conclusion
This defect will be fixed in: 7.0.0 SR7 6.0.1 SR8 . The JVM has been updated so that the compact reason for "failed to expand" is aggressive only if a subsequent scavenge leads to another percolate. If both "failed to expand" and "failed tenure" percolate conditions are met (which is often a case), "failed tenure" takes precedence. both are now treated equally, but the percolate reason in verbose gc will be reported as "failed tenure".
Temporary fix
Comments
APAR Information
APAR number
IV51086
Reported component name
J9 COMMON CODE
Reported component ID
620700127
Reported release
260
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2013-10-18
Closed date
2013-10-18
Last modified date
2013-10-21
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
J9 COMMON CODE
Fixed component ID
620700127
Applicable component levels
R260 PSY
UP
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Document Information
Modified date:
21 February 2022