1 /* 2 * Copyright (c) 2018, 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 #ifndef SHARE_VM_GC_PARALLEL_ADJOININGGENERATIONSFORHETEROHEAP_HPP 26 #define SHARE_VM_GC_PARALLEL_ADJOININGGENERATIONSFORHETEROHEAP_HPP 27 28 #include "gc/parallel/adjoiningGenerations.hpp" 29 30 class AdjoiningGenerationsForHeteroHeap : public AdjoiningGenerations { 31 friend class VMStructs; 32 private: 33 // Maximum total size of the generations. This is equal to the heap size specified by user. 34 // When adjusting young and old generation sizes, we need ensure that sum of the generation sizes does not exceed this. 35 size_t _total_size_limit; 36 37 size_t total_size_limit() const { 38 return _total_size_limit; 39 } 40 41 // HeteroVirtualSpaces creates non-overlapping virtual spaces. 42 // low() manages memory in nv-dimm and is meant for old generation. 43 // high() manages memory in dram and is meant for young generation. 44 class HeteroVirtualSpaces : public AdjoiningVirtualSpaces { 45 PSVirtualSpace* _young_vs; 46 PSVirtualSpace* _old_vs; 47 48 size_t _min_old_byte_size; 49 size_t _min_young_byte_size; 50 size_t _max_old_byte_size; 51 size_t _max_young_byte_size; 52 size_t _max_total_size; 53 54 public: 55 HeteroVirtualSpaces(ReservedSpace rs, 56 size_t min_old_byte_size, 57 size_t min_young_byte_size, size_t max_total_size, 58 size_t alignment); 59 60 PSVirtualSpace* high() { return _young_vs; } 61 PSVirtualSpace* low() { return _old_vs; } 62 // Increase old generation size and decrease young generation size by same amount 63 bool adjust_boundary_up(size_t size_in_bytes); 64 // Increase young generation size and decrease old generation size by same amount 65 bool adjust_boundary_down(size_t size_in_bytes); 66 67 size_t max_young_size() const { return _max_young_byte_size; } 68 size_t max_old_size() const { return _max_old_byte_size; } 69 70 void initialize(size_t initial_old_reserved_size, size_t init_low_byte_size, 71 size_t init_high_byte_size); 72 }; 73 74 public: 75 AdjoiningGenerationsForHeteroHeap(ReservedSpace rs, size_t total_size_limit, GenerationSizer* policy, size_t alignment); 76 77 // Given the size policy, calculate the total amount of memory that needs to be reserved. 78 // We need to reserve more memory than Xmx, since we use non-overlapping virtual spaces for the young and old generations. 79 static size_t required_reserved_memory(GenerationSizer* policy); 80 81 // Return the total byte size of the reserved space 82 size_t reserved_byte_size(); 83 }; 84 #endif // SHARE_VM_GC_PARALLEL_ADJOININGGENERATIONSFORHETEROHEAP_HPP 85