• file
• revisions
• annotate
• diff
• comparison
• raw

src/share/vm/memory/tenuredGeneration.hpp@122d10c82f3f (annotated)

src/share/vm/memory/tenuredGeneration.hpp

Wed, 29 Oct 2008 06:30:02 -0700

author

jcoomes

date

Wed, 29 Oct 2008 06:30:02 -0700

changeset 873

122d10c82f3f

parent 435

a61af66fc99e

child 905

ad8c8ca4ab0f

permissions

-rw-r--r--

6765804: GC "dead ratios" should be unsigned
Reviewed-by: ysr, tonyp

duke@435	1	/*
duke@435	2	* Copyright 2001-2007 Sun Microsystems, Inc. All Rights Reserved.
duke@435	3	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435	4	*
duke@435	5	* This code is free software; you can redistribute it and/or modify it
duke@435	6	* under the terms of the GNU General Public License version 2 only, as
duke@435	7	* published by the Free Software Foundation.
duke@435	8	*
duke@435	9	* This code is distributed in the hope that it will be useful, but WITHOUT
duke@435	10	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435	11	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435	12	* version 2 for more details (a copy is included in the LICENSE file that
duke@435	13	* accompanied this code).
duke@435	14	*
duke@435	15	* You should have received a copy of the GNU General Public License version
duke@435	16	* 2 along with this work; if not, write to the Free Software Foundation,
duke@435	17	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435	18	*
duke@435	19	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435	20	* CA 95054 USA or visit www.sun.com if you need additional information or
duke@435	21	* have any questions.
duke@435	22	*
duke@435	23	*/
duke@435	24
duke@435	25	// TenuredGeneration models the heap containing old (promoted/tenured) objects.
duke@435	26
duke@435	27	class ParGCAllocBufferWithBOT;
duke@435	28
duke@435	29	class TenuredGeneration: public OneContigSpaceCardGeneration {
duke@435	30	friend class VMStructs;
duke@435	31	protected:
duke@435	32	// current shrinking effect: this damps shrinking when the heap gets empty.
duke@435	33	size_t _shrink_factor;
duke@435	34	// Some statistics from before gc started.
duke@435	35	// These are gathered in the gc_prologue (and should_collect)
duke@435	36	// to control growing/shrinking policy in spite of promotions.
duke@435	37	size_t _capacity_at_prologue;
duke@435	38	size_t _used_at_prologue;
duke@435	39
duke@435	40	#ifndef SERIALGC
duke@435	41	// To support parallel promotion: an array of parallel allocation
duke@435	42	// buffers, one per thread, initially NULL.
duke@435	43	ParGCAllocBufferWithBOT** _alloc_buffers;
duke@435	44	#endif // SERIALGC
duke@435	45
duke@435	46	// Retire all alloc buffers before a full GC, so that they will be
duke@435	47	// re-allocated at the start of the next young GC.
duke@435	48	void retire_alloc_buffers_before_full_gc();
duke@435	49
duke@435	50	GenerationCounters* _gen_counters;
duke@435	51	CSpaceCounters* _space_counters;
duke@435	52
duke@435	53	public:
duke@435	54	TenuredGeneration(ReservedSpace rs, size_t initial_byte_size, int level,
duke@435	55	GenRemSet* remset);
duke@435	56
duke@435	57	Generation::Name kind() { return Generation::MarkSweepCompact; }
duke@435	58
duke@435	59	// Printing
duke@435	60	const char* name() const;
duke@435	61	const char* short_name() const { return "Tenured"; }
duke@435	62	bool must_be_youngest() const { return false; }
duke@435	63	bool must_be_oldest() const { return true; }
duke@435	64
duke@435	65	// Does a "full" (forced) collection invoked on this generation collect
duke@435	66	// all younger generations as well? Note that this is a
duke@435	67	// hack to allow the collection of the younger gen first if the flag is
duke@435	68	// set. This is better than using th policy's should_collect_gen0_first()
duke@435	69	// since that causes us to do an extra unnecessary pair of restart-&-stop-world.
duke@435	70	virtual bool full_collects_younger_generations() const {
duke@435	71	return !CollectGen0First;
duke@435	72	}
duke@435	73
duke@435	74	// Mark sweep support
duke@435	75	void compute_new_size();
duke@435	76
duke@435	77	virtual void gc_prologue(bool full);
duke@435	78	virtual void gc_epilogue(bool full);
duke@435	79	bool should_collect(bool full,
duke@435	80	size_t word_size,
duke@435	81	bool is_tlab);
duke@435	82
duke@435	83	virtual void collect(bool full,
duke@435	84	bool clear_all_soft_refs,
duke@435	85	size_t size,
duke@435	86	bool is_tlab);
duke@435	87
duke@435	88	#ifndef SERIALGC
duke@435	89	// Overrides.
duke@435	90	virtual oop par_promote(int thread_num,
duke@435	91	oop obj, markOop m, size_t word_sz);
duke@435	92	virtual void par_promote_alloc_undo(int thread_num,
duke@435	93	HeapWord* obj, size_t word_sz);
duke@435	94	virtual void par_promote_alloc_done(int thread_num);
duke@435	95	#endif // SERIALGC
duke@435	96
duke@435	97	// Performance Counter support
duke@435	98	void update_counters();
duke@435	99
duke@435	100	// Statistics
duke@435	101
duke@435	102	virtual void update_gc_stats(int level, bool full);
duke@435	103
duke@435	104	virtual bool promotion_attempt_is_safe(size_t max_promoted_in_bytes,
duke@435	105	bool younger_handles_promotion_failure) const;
duke@435	106
duke@435	107	void verify_alloc_buffers_clean();
duke@435	108	};