startCycle < minCycle (18MissWritebackEvent)

[CannotDeFine]

When I run bench cg of NPB, find somthing wrong. The following is the information:

 NAS Parallel Benchmarks (NPB3.3-OMP) - CG Benchmark

 Size:      150000


 Iterations:                     75
 NAS Parallel Benchmarks (NPB3.3-OMP) - CG Benchmark






 NAS Parallel Benchmarks (NPB3.3-OMP) - CG Benchmark
 NAS Parallel Benchmarks (NPB3.3-OMP) - CG Benchmark


 Size:      150000
 Iterations:                     75

 Size:      150000
 Size:      150000
 Iterations:                     75
 Iterations:                     75


[S 0] Failed assertion on build/opt/timing_event.h:160: startCycle 20057875325 < minStartCycle 20057875518 (18MissWritebackEvent), preDelay 0 postDelay 27 numChildren 0 str 
[S 0] [1] Internal exception detected:
[S 0] [1]  Code: 1
[S 0] [1]  Address: 0x7ffff6fd4713
[S 0] [1]  Description: Exception Code: ACCESS_INVALID_ADDRESS. Exception Address = 0x7ffff6fd4713. Access Type: UNKNOWN. Access Address = 0x000000000
[S 0] [1]  Caused by invalid access to address 0x0
[S 0] [1] Backtrace (10/40 max frames)
[S 0] [1]  /home/sy/cdf/data/zsim/build/opt/zsim.cpp:1394 / InternalExceptionHandler(unsigned int, LEVEL_BASE::EXCEPTION_INFO*, LEVEL_VM::PHYSICAL_CONTEXT*, void*)
[S 0] [1]  :? / LEVEL_PINCLIENT::IEH_CALLBACKS::NotifyInternalException(unsigned int, LEVEL_BASE::EXCEPTION_INFO*, LEVEL_VM::CONTEXT*)
[S 0] [1]  /home/sy/cdf/lib/pin-2.14-71313-gcc.4.4.7-linux/intel64/bin/pinbin(_ZN8LEVEL_VM12SIGNALS_IMPL19InternalHandlerSyncEiPN7BARECRT8SIGXINFOEPN5PINVM11ISIGCONTEXTEPPKNS_14SCT_ATTRIBUTESEPNS_5PCTXTEPj+0x444) [0x3043a9454]
[S 0] [1]  /home/sy/cdf/lib/pin-2.14-71313-gcc.4.4.7-linux/intel64/bin/pinbin(_ZN8LEVEL_VM12SIGNALS_IMPL20HandlePhysicalSignalEPN7BARECRT8SIGXINFOEPN5PINVM11ISIGCONTEXTE+0x124) [0x3043aa1f4]
[S 0] [1]  /home/sy/cdf/lib/pin-2.14-71313-gcc.4.4.7-linux/intel64/bin/pinbin(_ZN5PINVM28SIGNAL_DETAILS_LINUX_INTEL6415InternalHandlerEiPN7BARECRT8SIGXINFOEPv+0xe8) [0x304438c88]
[S 0] [1]  /home/sy/cdf/lib/pin-2.14-71313-gcc.4.4.7-linux/intel64/bin/pinbin(BARECRT_SigReturnRt+0) [0x30446603c]
[S 0] [1]  /home/sy/cdf/data/zsim/build/opt/timing_event.h:160 / TimingEvent::run(unsigned long)
[S 0] [1]  /home/sy/cdf/data/zsim/build/opt/contention_sim.cpp:282 / ContentionSim::simThreadLoop(unsigned int)
[S 0] [1]  /home/sy/cdf/lib/pin-2.14-71313-gcc.4.4.7-linux/intel64/bin/pinbin(_ZN8LEVEL_VM17VM_THREAD_DB_UNIX13THREAD_RUNNER9RunThreadEPN11OS_SERVICES7ITHREADE+0x289) [0x3043b3239]
[S 0] [1]  /home/sy/cdf/lib/pin-2.14-71313-gcc.4.4.7-linux/intel64/bin/pinbin(_ZN11OS_SERVICES6THREAD12RootFunctionEPv+0x26) [0x304465636]
C: Tool (or Pin) caused signal 11 at PC 0x7ffff6fd4713
[H] Child 2598997 done
[H] Panic on build/opt/zsim_harness.cpp:123: Child 2598997 (idx 0) exit was anomalous, killing simulation
[H] WARN: Hard death at exit (3 children running), killing the whole process tree

When I run it in one process, this error does not happened.