Application failure with traversal

[Lennart Börjeson]

> 9 feb. 2018 kl. 20:24 skrev Roman Kennke <rkennke at redhat.com>:
> 
> diff --git a/src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp
> b/src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp
> --- a/src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp
> +++ b/src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp
> @@ -1308,7 +1308,6 @@
>     FLAG_SET_DEFAULT(ShenandoahStoreValEnqueueBarrier, true);
>     FLAG_SET_DEFAULT(ShenandoahKeepAliveBarrier,       false);
>     FLAG_SET_DEFAULT(ShenandoahAsmWB,                  true);
> -    FLAG_SET_DEFAULT(ShenandoahBarriersForConst,       true);
>     FLAG_SET_DEFAULT(ShenandoahWriteBarrierRB,         false);
>     FLAG_SET_DEFAULT(ShenandoahAllocImplicitLive,      false);
>   }

I can't seem to get that patch to apply?

patching file src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp
Hunk #1 FAILED at 1308.
1 out of 1 hunk FAILED -- saving rejects to file src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp.rej


Anyway, I just commented out that line manually:

diff -r 16f17f40cecf src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp     Thu Feb 08 13:24:03 2018 +0100
+++ b/src/hotspot/share/gc/shenandoah/shenandoahCollectorPolicy.cpp     Fri Feb 09 20:50:36 2018 +0100
@@ -1308,7 +1308,7 @@
     FLAG_SET_DEFAULT(ShenandoahStoreValEnqueueBarrier, true);
     FLAG_SET_DEFAULT(ShenandoahKeepAliveBarrier,       false);
     FLAG_SET_DEFAULT(ShenandoahAsmWB,                  true);
-    FLAG_SET_DEFAULT(ShenandoahBarriersForConst,       true);
+    //    FLAG_SET_DEFAULT(ShenandoahBarriersForConst,       true);
     FLAG_SET_DEFAULT(ShenandoahWriteBarrierRB,         false);
     FLAG_SET_DEFAULT(ShenandoahAllocImplicitLive,      false);
   }


Anyway, with this change I don't get an NPE, but the application JVM crashes with this:


# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error (/home/lennartb/shenandoah-jdk10/src/hotspot/share/opto/split_if.cpp:173), pid=39409, tid=39425
#  assert(u_ctrl != blk1 && u_ctrl != blk2) failed: won't converge
#
# JRE version: OpenJDK Runtime Environment (10.0) (fastdebug build 10-internal+0-adhoc.lennartb.shenandoah-jdk10)
# Java VM: OpenJDK 64-Bit Server VM (fastdebug 10-internal+0-adhoc.lennartb.shenandoah-jdk10, mixed mode, tiered, compressed oops, Shenandoah gc, linux-amd64)
# Core dump will be written. Default location: /home/tetest/TE/system/cd1/core.39409
#
# If you would like to submit a bug report, please visit:
#   http://bugreport.java.com/bugreport/crash.jsp
#

---------------  S U M M A R Y ------------

Command Line: -Xms2400M -Xmx4800M -XX:+PrintFlagsFinal -Xlog:gc*=info,safepoint*=info,vmoperation*=trace:stdout:uptime,uptimenanos,timenanos,level,tags -XX:+UnlockExperimentalVMOptions -XX:SyncKnobs=Verbose=1 -XX:+PrintSafepointStatistics -XX:PrintSafepointStatisticsCount=1 -XX:+SafepointTimeout -XX:SafepointTimeoutDelay=1 --add-modules=java.xml.bind --add-exports=java.management/com.sun.jmx.mbeanserver=ALL-UNNAMED --add-exports=java.base/sun.nio.ch=ALL-UNNAMED -XX:+UseShenandoahGC -XX:ConcGCThreads=8 -XX:ParallelGCThreads=4 -XX:MonitorBound=20000 -XX:-UseBiasedLocking -XX:+DoEscapeAnalysis -XX:+UseNUMA -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=traversal -DRoundRobinPrio=0 -DHibernate3=true -DdumpConfig=VALUE -Djava.net.preferIPv4Stack=true -Djava.util.prefs.systemRoot=/home/tetest com.cinnober.framework.server.impl.FwStart --stdouttolog --stderrtolog -s CD1 -r http://frank-10g.cinnober.com:22780 -i TE -v com.cinnober.common.version.TeVersion

Host: frank.cinnober.com, Intel(R) Xeon(R) CPU E5-2687W v4 @ 3.00GHz, 48 cores, 503G, CentOS Linux release 7.3.1611 (Core) 
Time: Fri Feb  9 21:08:28 2018 CET elapsed time: 41 seconds (0d 0h 0m 41s)

---------------  T H R E A D  ---------------

Current thread (0x00007f7d6039e4a0):  JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=39425, stack(0x00007f7d114f6000,0x00007f7d115f7000)]


Current CompileTask:
C2:  41043 9019       4       com.mysql.jdbc.StringUtils::getInt (283 bytes)

Stack: [0x00007f7d114f6000,0x00007f7d115f7000],  sp=0x00007f7d115f02b0,  free space=1000k
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [libjvm.so+0x18af9ef]  VMError::report_and_die(int, char const*, char const*, __va_list_tag*, Thread*, unsigned char*, void*, void*, char const*, int, unsigned long)+0x15f
V  [libjvm.so+0x18b082a]  VMError::report_and_die(Thread*, char const*, int, char const*, char const*, __va_list_tag*)+0x4a
V  [libjvm.so+0xb15bca]  report_vm_error(char const*, int, char const*, char const*, ...)+0xea
V  [libjvm.so+0x17373ee]  PhaseIdealLoop::split_up(Node*, Node*, Node*) [clone .part.131]+0xe2e
V  [libjvm.so+0x1739c01]  PhaseIdealLoop::do_split_if(Node*)+0x8d1
V  [libjvm.so+0x114dcfb]  PhaseIdealLoop::split_if_with_blocks_post(Node*)+0xf8b
V  [libjvm.so+0x114ddab]  PhaseIdealLoop::split_if_with_blocks(VectorSet&, Node_Stack&)+0xab
V  [libjvm.so+0x11445f4]  PhaseIdealLoop::build_and_optimize(LoopOptsMode)+0x1494
V  [libjvm.so+0xa79f20]  Compile::optimize_loops(int&, PhaseIterGVN&, LoopOptsMode)+0x100
V  [libjvm.so+0xa82aa2]  Compile::Optimize()+0xe42
V  [libjvm.so+0xa84350]  Compile::Compile(ciEnv*, C2Compiler*, ciMethod*, int, bool, bool, bool, DirectiveSet*)+0x1460
V  [libjvm.so+0x8c41c3]  C2Compiler::compile_method(ciEnv*, ciMethod*, int, DirectiveSet*)+0x123
V  [libjvm.so+0xa9142d]  CompileBroker::invoke_compiler_on_method(CompileTask*)+0x35d
V  [libjvm.so+0xa924d8]  CompileBroker::compiler_thread_loop()+0x3b8
: