Mercurial > hg > graal-compiler
diff src/share/vm/memory/collectorPolicy.cpp @ 1387:0bfd3fb24150
6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
Summary: Ensure a full GC that clears SoftReferences before throwing an out-of-memory
Reviewed-by: ysr, jcoomes
author | jmasa |
---|---|
date | Tue, 13 Apr 2010 13:52:10 -0700 |
parents | 473cce303f13 |
children | c18cbe5936b8 |
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--- a/src/share/vm/memory/collectorPolicy.cpp Fri Apr 09 13:08:34 2010 -0400 +++ b/src/share/vm/memory/collectorPolicy.cpp Tue Apr 13 13:52:10 2010 -0700 @@ -1,5 +1,5 @@ /* - * Copyright 2001-2008 Sun Microsystems, Inc. All Rights Reserved. + * Copyright 2001-2010 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it @@ -112,6 +112,11 @@ } } +bool CollectorPolicy::use_should_clear_all_soft_refs(bool v) { + bool result = _should_clear_all_soft_refs; + set_should_clear_all_soft_refs(false); + return result; +} GenRemSet* CollectorPolicy::create_rem_set(MemRegion whole_heap, int max_covered_regions) { @@ -126,6 +131,17 @@ } } +void CollectorPolicy::cleared_all_soft_refs() { + // If near gc overhear limit, continue to clear SoftRefs. SoftRefs may + // have been cleared in the last collection but if the gc overhear + // limit continues to be near, SoftRefs should still be cleared. + if (size_policy() != NULL) { + _should_clear_all_soft_refs = size_policy()->gc_overhead_limit_near(); + } + _all_soft_refs_clear = true; +} + + // GenCollectorPolicy methods. size_t GenCollectorPolicy::scale_by_NewRatio_aligned(size_t base_size) { @@ -489,6 +505,12 @@ debug_only(gch->check_for_valid_allocation_state()); assert(gch->no_gc_in_progress(), "Allocation during gc not allowed"); + + // In general gc_overhead_limit_was_exceeded should be false so + // set it so here and reset it to true only if the gc time + // limit is being exceeded as checked below. + *gc_overhead_limit_was_exceeded = false; + HeapWord* result = NULL; // Loop until the allocation is satisified, @@ -524,12 +546,6 @@ return result; } - // There are NULL's returned for different circumstances below. - // In general gc_overhead_limit_was_exceeded should be false so - // set it so here and reset it to true only if the gc time - // limit is being exceeded as checked below. - *gc_overhead_limit_was_exceeded = false; - if (GC_locker::is_active_and_needs_gc()) { if (is_tlab) { return NULL; // Caller will retry allocating individual object @@ -568,18 +584,6 @@ gc_count_before = Universe::heap()->total_collections(); } - // Allocation has failed and a collection is about - // to be done. If the gc time limit was exceeded the - // last time a collection was done, return NULL so - // that an out-of-memory will be thrown. Clear - // gc_time_limit_exceeded so that subsequent attempts - // at a collection will be made. - if (size_policy()->gc_time_limit_exceeded()) { - *gc_overhead_limit_was_exceeded = true; - size_policy()->set_gc_time_limit_exceeded(false); - return NULL; - } - VM_GenCollectForAllocation op(size, is_tlab, gc_count_before); @@ -590,6 +594,24 @@ assert(result == NULL, "must be NULL if gc_locked() is true"); continue; // retry and/or stall as necessary } + + // Allocation has failed and a collection + // has been done. If the gc time limit was exceeded the + // this time, return NULL so that an out-of-memory + // will be thrown. Clear gc_overhead_limit_exceeded + // so that the overhead exceeded does not persist. + + const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); + const bool softrefs_clear = all_soft_refs_clear(); + assert(!limit_exceeded || softrefs_clear, "Should have been cleared"); + if (limit_exceeded && softrefs_clear) { + *gc_overhead_limit_was_exceeded = true; + size_policy()->set_gc_overhead_limit_exceeded(false); + if (op.result() != NULL) { + CollectedHeap::fill_with_object(op.result(), size); + } + return NULL; + } assert(result == NULL || gch->is_in_reserved(result), "result not in heap"); return result; @@ -688,6 +710,9 @@ return result; } + assert(!should_clear_all_soft_refs(), + "Flag should have been handled and cleared prior to this point"); + // What else? We might try synchronous finalization later. If the total // space available is large enough for the allocation, then a more // complete compaction phase than we've tried so far might be