src/hotspot/share/gc/parallel/adjoiningGenerations.cpp - platform/libcore - Git at Google

 /*
  * Copyright (c) 2003, 2015, Oracle and/or its affiliates. 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
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */

 #include "precompiled.hpp"
 #include "gc/parallel/adjoiningGenerations.hpp"
 #include "gc/parallel/adjoiningVirtualSpaces.hpp"
 #include "gc/parallel/generationSizer.hpp"
 #include "gc/parallel/parallelScavengeHeap.hpp"
 #include "logging/log.hpp"
 #include "logging/logStream.hpp"
 #include "memory/resourceArea.hpp"
 #include "utilities/align.hpp"
 #include "utilities/ostream.hpp"

 // If boundary moving is being used, create the young gen and old
 // gen with ASPSYoungGen and ASPSOldGen, respectively.  Revert to
 // the old behavior otherwise (with PSYoungGen and PSOldGen).

 AdjoiningGenerations::AdjoiningGenerations(ReservedSpace old_young_rs,
                                            GenerationSizer* policy,
                                            size_t alignment) :
   _virtual_spaces(old_young_rs, policy->min_old_size(),
                   policy->min_young_size(), alignment) {
   size_t init_low_byte_size = policy->initial_old_size();
   size_t min_low_byte_size = policy->min_old_size();
   size_t max_low_byte_size = policy->max_old_size();
   size_t init_high_byte_size = policy->initial_young_size();
   size_t min_high_byte_size = policy->min_young_size();
   size_t max_high_byte_size = policy->max_young_size();

   assert(min_low_byte_size <= init_low_byte_size &&
          init_low_byte_size <= max_low_byte_size, "Parameter check");
   assert(min_high_byte_size <= init_high_byte_size &&
          init_high_byte_size <= max_high_byte_size, "Parameter check");
   // Create the generations differently based on the option to
   // move the boundary.
   if (UseAdaptiveGCBoundary) {
     // Initialize the adjoining virtual spaces.  Then pass the
     // a virtual to each generation for initialization of the
     // generation.

     // Does the actual creation of the virtual spaces
     _virtual_spaces.initialize(max_low_byte_size,
                                init_low_byte_size,
                                init_high_byte_size);

     // Place the young gen at the high end.  Passes in the virtual space.
     _young_gen = new ASPSYoungGen(_virtual_spaces.high(),
                                   _virtual_spaces.high()->committed_size(),
                                   min_high_byte_size,
                                   _virtual_spaces.high_byte_size_limit());

     // Place the old gen at the low end. Passes in the virtual space.
     _old_gen = new ASPSOldGen(_virtual_spaces.low(),
                               _virtual_spaces.low()->committed_size(),
                               min_low_byte_size,
                               _virtual_spaces.low_byte_size_limit(),
                               "old", 1);

     young_gen()->initialize_work();
     assert(young_gen()->reserved().byte_size() <= young_gen()->gen_size_limit(),
      "Consistency check");
     assert(old_young_rs.size() >= young_gen()->gen_size_limit(),
      "Consistency check");

     old_gen()->initialize_work("old", 1);
     assert(old_gen()->reserved().byte_size() <= old_gen()->gen_size_limit(),
      "Consistency check");
     assert(old_young_rs.size() >= old_gen()->gen_size_limit(),
      "Consistency check");
   } else {

     // Layout the reserved space for the generations.
     ReservedSpace old_rs   =
       virtual_spaces()->reserved_space().first_part(max_low_byte_size);
     ReservedSpace heap_rs  =
       virtual_spaces()->reserved_space().last_part(max_low_byte_size);
     ReservedSpace young_rs = heap_rs.first_part(max_high_byte_size);
     assert(young_rs.size() == heap_rs.size(), "Didn't reserve all of the heap");

     // Create the generations.  Virtual spaces are not passed in.
     _young_gen = new PSYoungGen(init_high_byte_size,
                                 min_high_byte_size,
                                 max_high_byte_size);
     _old_gen = new PSOldGen(init_low_byte_size,
                             min_low_byte_size,
                             max_low_byte_size,
                             "old", 1);

     // The virtual spaces are created by the initialization of the gens.
     _young_gen->initialize(young_rs, alignment);
     assert(young_gen()->gen_size_limit() == young_rs.size(),
       "Consistency check");
     _old_gen->initialize(old_rs, alignment, "old", 1);
     assert(old_gen()->gen_size_limit() == old_rs.size(), "Consistency check");
   }
 }

 size_t AdjoiningGenerations::reserved_byte_size() {
   return virtual_spaces()->reserved_space().size();
 }

 void log_before_expansion(bool old, size_t expand_in_bytes, size_t change_in_bytes, size_t max_size) {
   Log(heap, ergo) log;
   if (!log.is_debug()) {
    return;
   }
   log.debug("Before expansion of %s gen with boundary move", old ? "old" : "young");
   log.debug("  Requested change: " SIZE_FORMAT_HEX "  Attempted change: " SIZE_FORMAT_HEX,
                         expand_in_bytes, change_in_bytes);
   ResourceMark rm;
   LogStream ls(log.debug());
   ParallelScavengeHeap::heap()->print_on(&ls);
   log.debug("  PS%sGen max size: " SIZE_FORMAT "K", old ? "Old" : "Young", max_size/K);
 }

 void log_after_expansion(bool old, size_t max_size) {
   Log(heap, ergo) log;
   if (!log.is_debug()) {
    return;
   }
   log.debug("After expansion of %s gen with boundary move", old ? "old" : "young");
   ResourceMark rm;
   LogStream ls(log.debug());
   ParallelScavengeHeap::heap()->print_on(&ls);
   log.debug("  PS%sGen max size: " SIZE_FORMAT "K", old ? "Old" : "Young", max_size/K);
 }

 // Make checks on the current sizes of the generations and
 // the constraints on the sizes of the generations.  Push
 // up the boundary within the constraints.  A partial
 // push can occur.
 void AdjoiningGenerations::request_old_gen_expansion(size_t expand_in_bytes) {
   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

   assert_lock_strong(ExpandHeap_lock);
   assert_locked_or_safepoint(Heap_lock);

   // These sizes limit the amount the boundaries can move.  Effectively,
   // the generation says how much it is willing to yield to the other
   // generation.
   const size_t young_gen_available = young_gen()->available_for_contraction();
   const size_t old_gen_available = old_gen()->available_for_expansion();
   const size_t alignment = virtual_spaces()->alignment();
   size_t change_in_bytes = MIN3(young_gen_available,
                                 old_gen_available,
                                 align_up(expand_in_bytes, alignment));

   if (change_in_bytes == 0) {
     return;
   }

   log_before_expansion(true, expand_in_bytes, change_in_bytes, old_gen()->max_gen_size());

   // Move the boundary between the generations up (smaller young gen).
   if (virtual_spaces()->adjust_boundary_up(change_in_bytes)) {
     young_gen()->reset_after_change();
     old_gen()->reset_after_change();
   }

   // The total reserved for the generations should match the sum
   // of the two even if the boundary is moving.
   assert(reserved_byte_size() ==
          old_gen()->max_gen_size() + young_gen()->max_size(),
          "Space is missing");
   young_gen()->space_invariants();
   old_gen()->space_invariants();

   log_after_expansion(true, old_gen()->max_gen_size());
 }

 // See comments on request_old_gen_expansion()
 bool AdjoiningGenerations::request_young_gen_expansion(size_t expand_in_bytes) {
   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

   // If eden is not empty, the boundary can be moved but no advantage
   // can be made of the move since eden cannot be moved.
   if (!young_gen()->eden_space()->is_empty()) {
     return false;
   }


   bool result = false;
   const size_t young_gen_available = young_gen()->available_for_expansion();
   const size_t old_gen_available = old_gen()->available_for_contraction();
   const size_t alignment = virtual_spaces()->alignment();
   size_t change_in_bytes = MIN3(young_gen_available,
                                 old_gen_available,
                                 align_up(expand_in_bytes, alignment));

   if (change_in_bytes == 0) {
     return false;
   }

   log_before_expansion(false, expand_in_bytes, change_in_bytes, young_gen()->max_size());

   // Move the boundary between the generations down (smaller old gen).
   MutexLocker x(ExpandHeap_lock);
   if (virtual_spaces()->adjust_boundary_down(change_in_bytes)) {
     young_gen()->reset_after_change();
     old_gen()->reset_after_change();
     result = true;
   }

   // The total reserved for the generations should match the sum
   // of the two even if the boundary is moving.
   assert(reserved_byte_size() ==
          old_gen()->max_gen_size() + young_gen()->max_size(),
          "Space is missing");
   young_gen()->space_invariants();
   old_gen()->space_invariants();

   log_after_expansion(false, young_gen()->max_size());

   return result;
 }

 // Additional space is needed in the old generation.  Try to move the boundary
 // up to meet the need.  Moves boundary up only
 void AdjoiningGenerations::adjust_boundary_for_old_gen_needs(
   size_t desired_free_space) {
   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

   // Stress testing.
   if (PSAdaptiveSizePolicyResizeVirtualSpaceAlot == 1) {
     MutexLocker x(ExpandHeap_lock);
     request_old_gen_expansion(virtual_spaces()->alignment() * 3 / 2);
   }

   // Expand only if the entire generation is already committed.
   if (old_gen()->virtual_space()->uncommitted_size() == 0) {
     if (old_gen()->free_in_bytes() < desired_free_space) {
       MutexLocker x(ExpandHeap_lock);
       request_old_gen_expansion(desired_free_space);
     }
   }
 }

 // See comment on adjust_boundary_for_old_gen_needss().
 // Adjust boundary down only.
 void AdjoiningGenerations::adjust_boundary_for_young_gen_needs(size_t eden_size,
     size_t survivor_size) {

   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

   // Stress testing.
   if (PSAdaptiveSizePolicyResizeVirtualSpaceAlot == 0) {
     request_young_gen_expansion(virtual_spaces()->alignment() * 3 / 2);
     eden_size = young_gen()->eden_space()->capacity_in_bytes();
   }

   // Expand only if the entire generation is already committed.
   if (young_gen()->virtual_space()->uncommitted_size() == 0) {
     size_t desired_size = eden_size + 2 * survivor_size;
     const size_t committed = young_gen()->virtual_space()->committed_size();
     if (desired_size > committed) {
       request_young_gen_expansion(desired_size - committed);
     }
   }
 }
	/*
	* Copyright (c) 2003, 2015, Oracle and/or its affiliates. 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
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*
	*/

	#include "precompiled.hpp"
	#include "gc/parallel/adjoiningGenerations.hpp"
	#include "gc/parallel/adjoiningVirtualSpaces.hpp"
	#include "gc/parallel/generationSizer.hpp"
	#include "gc/parallel/parallelScavengeHeap.hpp"
	#include "logging/log.hpp"
	#include "logging/logStream.hpp"
	#include "memory/resourceArea.hpp"
	#include "utilities/align.hpp"
	#include "utilities/ostream.hpp"

	// If boundary moving is being used, create the young gen and old
	// gen with ASPSYoungGen and ASPSOldGen, respectively. Revert to
	// the old behavior otherwise (with PSYoungGen and PSOldGen).

	AdjoiningGenerations::AdjoiningGenerations(ReservedSpace old_young_rs,
	GenerationSizer* policy,
	size_t alignment) :
	_virtual_spaces(old_young_rs, policy->min_old_size(),
	policy->min_young_size(), alignment) {
	size_t init_low_byte_size = policy->initial_old_size();
	size_t min_low_byte_size = policy->min_old_size();
	size_t max_low_byte_size = policy->max_old_size();
	size_t init_high_byte_size = policy->initial_young_size();
	size_t min_high_byte_size = policy->min_young_size();
	size_t max_high_byte_size = policy->max_young_size();

	assert(min_low_byte_size <= init_low_byte_size &&
	init_low_byte_size <= max_low_byte_size, "Parameter check");
	assert(min_high_byte_size <= init_high_byte_size &&
	init_high_byte_size <= max_high_byte_size, "Parameter check");
	// Create the generations differently based on the option to
	// move the boundary.
	if (UseAdaptiveGCBoundary) {
	// Initialize the adjoining virtual spaces. Then pass the
	// a virtual to each generation for initialization of the
	// generation.

	// Does the actual creation of the virtual spaces
	_virtual_spaces.initialize(max_low_byte_size,
	init_low_byte_size,
	init_high_byte_size);

	// Place the young gen at the high end. Passes in the virtual space.
	_young_gen = new ASPSYoungGen(_virtual_spaces.high(),
	_virtual_spaces.high()->committed_size(),
	min_high_byte_size,
	_virtual_spaces.high_byte_size_limit());

	// Place the old gen at the low end. Passes in the virtual space.
	_old_gen = new ASPSOldGen(_virtual_spaces.low(),
	_virtual_spaces.low()->committed_size(),
	min_low_byte_size,
	_virtual_spaces.low_byte_size_limit(),
	"old", 1);

	young_gen()->initialize_work();
	assert(young_gen()->reserved().byte_size() <= young_gen()->gen_size_limit(),
	"Consistency check");
	assert(old_young_rs.size() >= young_gen()->gen_size_limit(),
	"Consistency check");

	old_gen()->initialize_work("old", 1);
	assert(old_gen()->reserved().byte_size() <= old_gen()->gen_size_limit(),
	"Consistency check");
	assert(old_young_rs.size() >= old_gen()->gen_size_limit(),
	"Consistency check");
	} else {

	// Layout the reserved space for the generations.
	ReservedSpace old_rs =
	virtual_spaces()->reserved_space().first_part(max_low_byte_size);
	ReservedSpace heap_rs =
	virtual_spaces()->reserved_space().last_part(max_low_byte_size);
	ReservedSpace young_rs = heap_rs.first_part(max_high_byte_size);
	assert(young_rs.size() == heap_rs.size(), "Didn't reserve all of the heap");

	// Create the generations. Virtual spaces are not passed in.
	_young_gen = new PSYoungGen(init_high_byte_size,
	min_high_byte_size,
	max_high_byte_size);
	_old_gen = new PSOldGen(init_low_byte_size,
	min_low_byte_size,
	max_low_byte_size,
	"old", 1);

	// The virtual spaces are created by the initialization of the gens.
	_young_gen->initialize(young_rs, alignment);
	assert(young_gen()->gen_size_limit() == young_rs.size(),
	"Consistency check");
	_old_gen->initialize(old_rs, alignment, "old", 1);
	assert(old_gen()->gen_size_limit() == old_rs.size(), "Consistency check");
	}
	}

	size_t AdjoiningGenerations::reserved_byte_size() {
	return virtual_spaces()->reserved_space().size();
	}

	void log_before_expansion(bool old, size_t expand_in_bytes, size_t change_in_bytes, size_t max_size) {
	Log(heap, ergo) log;
	if (!log.is_debug()) {
	return;
	}
	log.debug("Before expansion of %s gen with boundary move", old ? "old" : "young");
	log.debug(" Requested change: " SIZE_FORMAT_HEX " Attempted change: " SIZE_FORMAT_HEX,
	expand_in_bytes, change_in_bytes);
	ResourceMark rm;
	LogStream ls(log.debug());
	ParallelScavengeHeap::heap()->print_on(&ls);
	log.debug(" PS%sGen max size: " SIZE_FORMAT "K", old ? "Old" : "Young", max_size/K);
	}

	void log_after_expansion(bool old, size_t max_size) {
	Log(heap, ergo) log;
	if (!log.is_debug()) {
	return;
	}
	log.debug("After expansion of %s gen with boundary move", old ? "old" : "young");
	ResourceMark rm;
	LogStream ls(log.debug());
	ParallelScavengeHeap::heap()->print_on(&ls);
	log.debug(" PS%sGen max size: " SIZE_FORMAT "K", old ? "Old" : "Young", max_size/K);
	}

	// Make checks on the current sizes of the generations and
	// the constraints on the sizes of the generations. Push
	// up the boundary within the constraints. A partial
	// push can occur.
	void AdjoiningGenerations::request_old_gen_expansion(size_t expand_in_bytes) {
	assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

	assert_lock_strong(ExpandHeap_lock);
	assert_locked_or_safepoint(Heap_lock);

	// These sizes limit the amount the boundaries can move. Effectively,
	// the generation says how much it is willing to yield to the other
	// generation.
	const size_t young_gen_available = young_gen()->available_for_contraction();
	const size_t old_gen_available = old_gen()->available_for_expansion();
	const size_t alignment = virtual_spaces()->alignment();
	size_t change_in_bytes = MIN3(young_gen_available,
	old_gen_available,
	align_up(expand_in_bytes, alignment));

	if (change_in_bytes == 0) {
	return;
	}

	log_before_expansion(true, expand_in_bytes, change_in_bytes, old_gen()->max_gen_size());

	// Move the boundary between the generations up (smaller young gen).
	if (virtual_spaces()->adjust_boundary_up(change_in_bytes)) {
	young_gen()->reset_after_change();
	old_gen()->reset_after_change();
	}

	// The total reserved for the generations should match the sum
	// of the two even if the boundary is moving.
	assert(reserved_byte_size() ==
	old_gen()->max_gen_size() + young_gen()->max_size(),
	"Space is missing");
	young_gen()->space_invariants();
	old_gen()->space_invariants();

	log_after_expansion(true, old_gen()->max_gen_size());
	}

	// See comments on request_old_gen_expansion()
	bool AdjoiningGenerations::request_young_gen_expansion(size_t expand_in_bytes) {
	assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

	// If eden is not empty, the boundary can be moved but no advantage
	// can be made of the move since eden cannot be moved.
	if (!young_gen()->eden_space()->is_empty()) {
	return false;
	}


	bool result = false;
	const size_t young_gen_available = young_gen()->available_for_expansion();
	const size_t old_gen_available = old_gen()->available_for_contraction();
	const size_t alignment = virtual_spaces()->alignment();
	size_t change_in_bytes = MIN3(young_gen_available,
	old_gen_available,
	align_up(expand_in_bytes, alignment));

	if (change_in_bytes == 0) {
	return false;
	}

	log_before_expansion(false, expand_in_bytes, change_in_bytes, young_gen()->max_size());

	// Move the boundary between the generations down (smaller old gen).
	MutexLocker x(ExpandHeap_lock);
	if (virtual_spaces()->adjust_boundary_down(change_in_bytes)) {
	young_gen()->reset_after_change();
	old_gen()->reset_after_change();
	result = true;
	}

	// The total reserved for the generations should match the sum
	// of the two even if the boundary is moving.
	assert(reserved_byte_size() ==
	old_gen()->max_gen_size() + young_gen()->max_size(),
	"Space is missing");
	young_gen()->space_invariants();
	old_gen()->space_invariants();

	log_after_expansion(false, young_gen()->max_size());

	return result;
	}

	// Additional space is needed in the old generation. Try to move the boundary
	// up to meet the need. Moves boundary up only
	void AdjoiningGenerations::adjust_boundary_for_old_gen_needs(
	size_t desired_free_space) {
	assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

	// Stress testing.
	if (PSAdaptiveSizePolicyResizeVirtualSpaceAlot == 1) {
	MutexLocker x(ExpandHeap_lock);
	request_old_gen_expansion(virtual_spaces()->alignment() * 3 / 2);
	}

	// Expand only if the entire generation is already committed.
	if (old_gen()->virtual_space()->uncommitted_size() == 0) {
	if (old_gen()->free_in_bytes() < desired_free_space) {
	MutexLocker x(ExpandHeap_lock);
	request_old_gen_expansion(desired_free_space);
	}
	}
	}

	// See comment on adjust_boundary_for_old_gen_needss().
	// Adjust boundary down only.
	void AdjoiningGenerations::adjust_boundary_for_young_gen_needs(size_t eden_size,
	size_t survivor_size) {

	assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");

	// Stress testing.
	if (PSAdaptiveSizePolicyResizeVirtualSpaceAlot == 0) {
	request_young_gen_expansion(virtual_spaces()->alignment() * 3 / 2);
	eden_size = young_gen()->eden_space()->capacity_in_bytes();
	}

	// Expand only if the entire generation is already committed.
	if (young_gen()->virtual_space()->uncommitted_size() == 0) {
	size_t desired_size = eden_size + 2 * survivor_size;
	const size_t committed = young_gen()->virtual_space()->committed_size();
	if (desired_size > committed) {
	request_young_gen_expansion(desired_size - committed);
	}
	}
	}