// This method contains all heap specific policy for invoking mark sweep. // PSMarkSweep::invoke_no_policy() will only attempt to mark-sweep-compact // the heap. It will do nothing further. If we need to bail out for policy // reasons, scavenge before full gc, or any other specialized behavior, it // needs to be added here. // // Note that this method should only be called from the vm_thread while // at a safepoint! void PSMarkSweep::invoke(bool maximum_heap_compaction) { assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); assert(!Universe::heap()->is_gc_active(), "not reentrant"); ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); GCCause::Cause gc_cause = heap->gc_cause(); PSAdaptiveSizePolicy* policy = heap->size_policy(); // Before each allocation/collection attempt, find out from the // policy object if GCs are, on the whole, taking too long. If so, // bail out without attempting a collection. The exceptions are // for explicitly requested GC's. if (!policy->gc_time_limit_exceeded() || GCCause::is_user_requested_gc(gc_cause) || GCCause::is_serviceability_requested_gc(gc_cause)) { IsGCActiveMark mark; if (ScavengeBeforeFullGC) { PSScavenge::invoke_no_policy(); } int count = (maximum_heap_compaction)?1:MarkSweepAlwaysCompactCount; IntFlagSetting flag_setting(MarkSweepAlwaysCompactCount, count); PSMarkSweep::invoke_no_policy(maximum_heap_compaction); } }
// This method contains all heap specific policy for invoking scavenge. // PSScavenge::invoke_no_policy() will do nothing but attempt to // scavenge. It will not clean up after failed promotions, bail out if // we've exceeded policy time limits, or any other special behavior. // All such policy should be placed here. // // Note that this method should only be called from the vm_thread while // at a safepoint! void PSScavenge::invoke() { assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); assert(!Universe::heap()->is_gc_active(), "not reentrant"); ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); PSAdaptiveSizePolicy* policy = heap->size_policy(); // Before each allocation/collection attempt, find out from the // policy object if GCs are, on the whole, taking too long. If so, // bail out without attempting a collection. if (!policy->gc_time_limit_exceeded()) { IsGCActiveMark mark; bool scavenge_was_done = PSScavenge::invoke_no_policy(); PSGCAdaptivePolicyCounters* counters = heap->gc_policy_counters(); if (UsePerfData) counters->update_full_follows_scavenge(0); if (!scavenge_was_done || policy->should_full_GC(heap->old_gen()->free_in_bytes())) { if (UsePerfData) counters->update_full_follows_scavenge(full_follows_scavenge); GCCauseSetter gccs(heap, GCCause::_adaptive_size_policy); if (UseParallelOldGC) { PSParallelCompact::invoke_no_policy(false); } else { PSMarkSweep::invoke_no_policy(false); } } } }