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Bug ID: 7118648 disable compressed oops by default on MacOS X until 7118647 is fixed
7118648 : disable compressed oops by default on MacOS X until 7118647 is fixed

Details
Type:
Bug
Submit Date:
2011-12-06
Status:
Closed
Updated Date:
2012-03-22
Project Name:
JDK
Resolved Date:
2012-01-20
Component:
hotspot
OS:
os_x
Sub-Component:
runtime
CPU:
x86
Priority:
P3
Resolution:
Fixed
Affected Versions:
hs23
Fixed Versions:
hs23

Related Reports
Backport:
JDK-2219004 - disable compressed oops by default on MacOS X until 7118647 is fixed
Backport:
JDK-2219048 - disable compressed oops by default on MacOS X until 7118647 is fixed
Relates:
JDK-7142181 - MacOS: assert: noaccess_prefix should be used only with non zero based compressed oops

Sub Tasks

Description
Compressed oops should be disabled by default on MacOS X until the
following bug is fixed:

7118647 3/3 compressed oops crashes on MacOS X with JPRT GCBasher test

Comments
EVALUATION

http://hg.openjdk.java.net/lambda/lambda/hotspot/rev/55d777c0860a
2012-03-22 
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-emb/hotspot/rev/55d777c0860a
2011-12-15 
SUGGESTED FIX

This prevents the flag from being turned on:

set_ergonomics_flags();
+ #ifdef __APPLE__
+ UNSUPPORTED_OPTION(UseCompressedOops, "UseCompressedOops, pending the fix for 7118647,")
+ #endif
2011-12-07 
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-rt/hotspot/rev/55d777c0860a
2011-12-07 
EVALUATION

See description and suggested fix.
2011-12-06 
SUGGESTED FIX

Here are the context diffs for the proposed fix:

diff -r a5a9db0e0203 src/share/vm/runtime/arguments.cpp
--- a/src/share/vm/runtime/arguments.cpp        Tue Dec 06 07:23:42 2011 -0800
+++ b/src/share/vm/runtime/arguments.cpp        Tue Dec 06 15:29:17 2011 -0800
@@ -1359,9 +1359,12 @@
   // by ergonomics.
   if (MaxHeapSize <= max_heap_for_compressed_oops()) {
 #if !defined(COMPILER1) || defined(TIERED)
+#ifndef __APPLE__
+    // disable UseCompressedOops by default on MacOS X until 7118647 is fixed
     if (FLAG_IS_DEFAULT(UseCompressedOops)) {
       FLAG_SET_ERGO(bool, UseCompressedOops, true);
     }
+#endif // !__APPLE__
 #endif
 #ifdef _WIN64
     if (UseLargePages && UseCompressedOops) {
2011-12-06


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