1 /*
   2  * Copyright (c) 2001, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "gc/g1/g1Analytics.hpp"
  27 #include "gc/g1/g1CollectorPolicy.hpp"
  28 #include "gc/g1/g1YoungGenSizer.hpp"
  29 #include "gc/g1/heapRegion.hpp"
  30 #include "gc/g1/heapRegionRemSet.hpp"
  31 #include "gc/shared/gcPolicyCounters.hpp"
  32 #include "runtime/globals.hpp"
  33 #include "utilities/debug.hpp"
  34 
  35 G1CollectorPolicy::G1CollectorPolicy() {
  36 
  37   // Set up the region size and associated fields. Given that the
  38   // policy is created before the heap, we have to set this up here,
  39   // so it's done as soon as possible.
  40 
  41   // It would have been natural to pass initial_heap_byte_size() and
  42   // max_heap_byte_size() to setup_heap_region_size() but those have
  43   // not been set up at this point since they should be aligned with
  44   // the region size. So, there is a circular dependency here. We base
  45   // the region size on the heap size, but the heap size should be
  46   // aligned with the region size. To get around this we use the
  47   // unaligned values for the heap.
  48   HeapRegion::setup_heap_region_size(InitialHeapSize, MaxHeapSize);
  49   HeapRegionRemSet::setup_remset_size();
  50 }
  51 
  52 void G1CollectorPolicy::initialize_alignments() {
  53   _space_alignment = HeapRegion::GrainBytes;
  54   size_t card_table_alignment = CardTableRS::ct_max_alignment_constraint();
  55   size_t page_size = UseLargePages ? os::large_page_size() : os::vm_page_size();
  56   _heap_alignment = MAX3(card_table_alignment, _space_alignment, page_size);
  57 }
  58 
  59 size_t G1CollectorPolicy::heap_reservation_size_bytes() {
  60   return _max_heap_byte_size;
  61 }
  62 
  63 G1HeteroCollectorPolicy::G1HeteroCollectorPolicy() : _heap_reservation_size_bytes(MaxHeapSize*2) {
  64 }
  65 
  66 void G1HeteroCollectorPolicy::initialize_size_info() {
  67   G1CollectorPolicy::initialize_size_info();
  68   _heap_reservation_size_bytes = 2 * _max_heap_byte_size;
  69 }
  70 
  71 size_t G1HeteroCollectorPolicy::heap_reservation_size_bytes() {
  72   return _heap_reservation_size_bytes;
  73 }