--- old/src/hotspot/share/services/memoryManager.cpp 2018-10-08 18:33:27.000000000 -0400 +++ new/src/hotspot/share/services/memoryManager.cpp 2018-10-08 18:33:26.000000000 -0400 @@ -210,7 +210,10 @@ void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage, bool recordAccumulatedGCTime) { - assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking"); + // Inactive memory managers (young, mixed, and concurrent in G1 legacy mode, + // and incremental in G1 default mode) will not be initialized. + if (_last_gc_stat == NULL && _current_gc_stat == NULL) return; + if (recordAccumulatedGCTime) { _accumulated_timer.start(); } @@ -243,6 +246,8 @@ bool recordGCEndTime, bool countCollection, GCCause::Cause cause, bool allMemoryPoolsAffected) { + if (_last_gc_stat == NULL && _current_gc_stat == NULL) return; + if (recordAccumulatedGCTime) { _accumulated_timer.stop(); }