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Hi everyone,<br>
<br>
Could I have a couple of reviews for this change to remove some
unused debugging code?<br>
<br>
<a class="moz-txt-link-freetext" href="http://cr.openjdk.java.net/~brutisso/8141530/webrev.00/">http://cr.openjdk.java.net/~brutisso/8141530/webrev.00/</a><br>
<a class="moz-txt-link-freetext" href="https://bugs.openjdk.java.net/browse/JDK-8141530">https://bugs.openjdk.java.net/browse/JDK-8141530</a><br>
<br>
Thanks,<br>
Bengt<br>
<br>
From the bug report:<br>
<br>
<div class="mod-content">
<div title="Click to edit" id="description-val"
class="field-ignore-highlight editable-field inactive">
<div class="user-content-block"> The two develop flags
G1RecordHRRSOops and G1RecordHRRSEvents seem to have been
added to record information about remembered set management
that could be useful for debugging.
<br>
<br>
The information they record is never printed.
(HeapRegionRemSet::print_recorded() is never called in the
code). Thus the only use case must be to call the print method
from a debugging session, such as for example in gdb.
<br>
<br>
When I call HeapRegionRemSet::print_recorded() from gdb I get
a SIGSEGV. Same if I add a call to it from the end of a GC.
See the partial hs_err file below.
<br>
<br>
Since this is broken debugging code that uses logging I think
it is better to remove it than to try to fix it and update it
to use the unified logging framework.
<br>
<br>
#
<br>
# A fatal error has been detected by the Java Runtime
Environment:
<br>
#
<br>
# SIGSEGV (0xb) at pc=0x00007ffff6461f3e, pid=9436, tid=9495
<br>
#
<br>
# JRE version: Java(TM) SE Runtime Environment (9.0) (build
1.9.0-internal-fastdebug-brutisso_2015_10_30_09_20-b00)
<br>
# Java VM: Java HotSpot(TM) 64-Bit Server VM
(1.9.0-internal-fastdebug-brutisso_2015_10_30_09_20-b00, mixed
mode, tiered, compressed oops, g1 gc, linux-amd64)
<br>
# Problematic frame:
<br>
# V [libjvm.so+0xa8cf3e]
HeapRegionRemSet::print_recorded()+0x13e
<br>
#
<br>
# Core dump will be written. Default location: Core dumps may
be processed with "/usr/share/apport/apport %p %s %c %P" (or
dumping to /localhome/repos/jdk9-hs-rt/hotspot/core.9436)
<br>
#
<br>
# If you would like to submit a bug report, please visit:
<br>
# <a title="Follow link"
href="http://bugreport.java.com/bugreport/crash.jsp">http://bugreport.java.com/bugreport/crash.jsp</a>
<br>
#
<br>
<br>
--------------- S U M M A R Y ------------
<br>
<br>
Command Line: -Xmx128m -XX:+UseG1GC -XX:+G1RecordHRRSOops
-XX:+G1RecordHRRSEvents -XX:+G1TraceHeapRegionRememberedSet
TestGCOld 50 1 20 10 10000
<br>
<br>
Host: sthws37, Intel(R) Xeon(R) CPU E5-2665 0 @ 2.40GHz, 32
cores, 31G, Ubuntu 14.04.3 LTS
<br>
Time: Thu Nov 5 12:53:47 2015 CET elapsed time: 81 seconds (0d
0h 1m 21s)
<br>
<br>
--------------- T H R E A D ---------------
<br>
<br>
Current thread (0x00007ffff02c8000): VMThread [stack:
0x00007fff00200000,0x00007fff00301000] [id=9495]
<br>
<br>
Stack: [0x00007fff00200000,0x00007fff00301000],
sp=0x00007fff002ff840, free space=1022k
<br>
Native frames: (J=compiled Java code, j=interpreted, Vv=VM
code, C=native code)
<br>
V [libjvm.so+0xa8cf3e]
HeapRegionRemSet::print_recorded()+0x13e
<br>
V [libjvm.so+0x974c5d]
G1CollectedHeap::do_collection_pause_at_safepoint(double)+0xf6d
<br>
V [libjvm.so+0x125c09a] VM_G1IncCollectionPause::doit()+0xca
<br>
V [libjvm.so+0x125a455] VM_Operation::evaluate()+0xa5
<br>
V [libjvm.so+0x1257be4]
VMThread::evaluate_operation(VM_Operation*)+0x154
<br>
V [libjvm.so+0x1258513] VMThread::loop()+0x4c3
<br>
V [libjvm.so+0x125874b] VMThread::run()+0xbb
<br>
V [libjvm.so+0xf5049a] java_start(Thread*)+0xca
<br>
</div>
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