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Bug ID: 6962931 move interned strings out of the perm gen
6962931 : move interned strings out of the perm gen

Details
Type:
Enhancement
Submit Date:
2010-06-22
Status:
Resolved
Updated Date:
2011-05-25
Project Name:
JDK
Resolved Date:
2011-04-01
Component:
hotspot
OS:
solaris_2.5.1,generic
Sub-Component:
gc
CPU:
generic
Priority:
P3
Resolution:
Fixed
Affected Versions:
hs19,1.4.1
Fixed Versions:
hs21

Related Reports
Backport:
JDK-2208436 - move interned strings out of the perm gen
Duplicate:
JDK-4642821 - Keep interned strings out of perm gen
Relates:
JDK-6962930 - make the string table size configurable
Relates:
JDK-7028374 - race in fix_oop_relocations for scavengeable nmethods
Relates:
JDK-7032129 - Native memory usage grow unexpectedly for vm/oom/*InternedString tests
Relates:
JDK-7108242 - jinfo -permstat shouldn't report interned strings as part of perm
Relates:
JDK-7199147 - description of interned String in doc. of jmap -permstat needs changes
Relates:
JDK-7005510 - DynamicProbes01 fails with "assert(DTraceAllocProbes) failed: wrong call"
Relates:
JDK-6863023 - need non-perm oops in code cache for JSR 292

Sub Tasks

Description
Interned strings are currently stored in the permanent generation.  A new approach for managing meta-data is being designed and it requires interned strings to live elsewhere in the the heap (young gen and/or old gen).

Comments
EVALUATION

Some very intermittent failures were detected when testing these changes which turned out to be due to an existing bug in the non-perm oops code, fixed by 7028374.  So if this fix is ever backported, it should be accompanied by the fix for 7028374.
2011-04-16 
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot/hotspot/rev/b099aaf51bf8
2011-03-25 
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-rt/hotspot/rev/b099aaf51bf8
2011-03-25 
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-comp/hotspot/rev/b099aaf51bf8
2011-03-25 
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-gc/hotspot/rev/b099aaf51bf8
2011-03-22 
EVALUATION

See description.  This is straightforward since the fix for 6863023 removed the restriction that interned strings must reside in the perm gen.
2010-06-22


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