| /* |
| * Copyright (c) 2018, 2019, 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 |
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| */ |
| |
| #ifndef SHARE_GC_G1_HETEROGENEOUSHEAPREGIONMANAGER_HPP |
| #define SHARE_GC_G1_HETEROGENEOUSHEAPREGIONMANAGER_HPP |
| |
| #include "gc/g1/heapRegionManager.hpp" |
| |
| // This class manages heap regions on heterogenous memory comprising of dram and nv-dimm. |
| // Regions in dram (dram_set) are used for young objects and archive regions (CDS). |
| // Regions in nv-dimm (nvdimm_set) are used for old objects and humongous objects. |
| // At any point there are some regions committed on dram and some on nv-dimm with the following guarantees: |
| // 1. The total number of regions committed in dram and nv-dimm equals the current size of heap. |
| // 2. Consequently, total number of regions committed is less than or equal to Xmx. |
| // 3. To maintain the guarantee stated by 1., whenever one set grows (new regions committed), the other set shrinks (regions un-committed). |
| // 3a. If more dram regions are needed (young generation expansion), corresponding number of regions in nv-dimm are un-committed. |
| // 3b. When old generation or humongous set grows, and new regions need to be committed to nv-dimm, corresponding number of regions |
| // are un-committed in dram. |
| class HeterogeneousHeapRegionManager : public HeapRegionManager { |
| const uint _max_regions; |
| uint _max_dram_regions; |
| uint _max_nvdimm_regions; |
| uint _start_index_of_nvdimm; |
| uint _total_commited_before_full_gc; |
| uint _no_borrowed_regions; |
| |
| uint total_regions_committed() const; |
| uint num_committed_dram() const; |
| uint num_committed_nvdimm() const; |
| |
| // Similar to find_unavailable_from_idx() function from base class, difference is this function searches in range [start, end]. |
| uint find_unavailable_in_range(uint start_idx, uint end_idx, uint* res_idx) const; |
| |
| // Expand into dram. Maintains the invariant that total number of committed regions is less than current heap size. |
| uint expand_dram(uint num_regions, WorkGang* pretouch_workers); |
| |
| // Expand into nv-dimm. |
| uint expand_nvdimm(uint num_regions, WorkGang* pretouch_workers); |
| |
| // Expand by finding unavailable regions in [start, end] range. |
| uint expand_in_range(uint start, uint end, uint num_regions, WorkGang* pretouch_workers); |
| |
| // Shrink dram set of regions. |
| uint shrink_dram(uint num_regions, bool update_free_list = true); |
| |
| // Shrink nv-dimm set of regions. |
| uint shrink_nvdimm(uint num_regions, bool update_free_list = true); |
| |
| // Shrink regions from [start, end] range. |
| uint shrink_in_range(uint start, uint end, uint num_regions, bool update_free_list = true); |
| |
| // Similar to find_empty_from_idx_reverse() in base class. Only here it searches in a range. |
| uint find_empty_in_range_reverse(uint start_idx, uint end_idx, uint* res_idx); |
| |
| // Similar to find_contiguous() in base class, with [start, end] range |
| uint find_contiguous(size_t start, size_t end, size_t num, bool empty_only); |
| |
| // This function is called when there are no free nv-dimm regions. |
| // It borrows a region from the set of unavailable regions in nv-dimm for GC purpose. |
| HeapRegion* borrow_old_region_for_gc(); |
| |
| uint free_list_dram_length() const; |
| uint free_list_nvdimm_length() const; |
| |
| // is region with given index in nv-dimm? |
| bool is_in_nvdimm(uint index) const; |
| bool is_in_dram(uint index) const; |
| |
| public: |
| |
| // Empty constructor, we'll initialize it with the initialize() method. |
| HeterogeneousHeapRegionManager(uint num_regions) : _max_regions(num_regions), _max_dram_regions(0), |
| _max_nvdimm_regions(0), _start_index_of_nvdimm(0), |
| _total_commited_before_full_gc(0), _no_borrowed_regions(0) |
| {} |
| |
| static HeterogeneousHeapRegionManager* manager(); |
| |
| virtual void initialize(G1RegionToSpaceMapper* heap_storage, |
| G1RegionToSpaceMapper* prev_bitmap, |
| G1RegionToSpaceMapper* next_bitmap, |
| G1RegionToSpaceMapper* bot, |
| G1RegionToSpaceMapper* cardtable, |
| G1RegionToSpaceMapper* card_counts); |
| |
| uint start_index_of_nvdimm() const; |
| uint start_index_of_dram() const; |
| uint end_index_of_nvdimm() const; |
| uint end_index_of_dram() const; |
| |
| // Override. |
| HeapRegion* get_dummy_region(); |
| |
| // Adjust dram_set to provision 'expected_num_regions' regions. |
| void adjust_dram_regions(uint expected_num_regions, WorkGang* pretouch_workers); |
| |
| // Prepare heap regions before and after full collection. |
| void prepare_for_full_collection_start(); |
| void prepare_for_full_collection_end(); |
| |
| virtual HeapRegion* allocate_free_region(HeapRegionType type); |
| |
| // Return maximum number of regions that heap can expand to. |
| uint max_expandable_length() const; |
| |
| // Override. Expand in nv-dimm. |
| uint expand_by(uint num_regions, WorkGang* pretouch_workers); |
| |
| // Override. |
| uint expand_at(uint start, uint num_regions, WorkGang* pretouch_workers); |
| |
| // Override. This function is called for humongous allocation, so we need to find empty regions in nv-dimm. |
| uint find_contiguous_only_empty(size_t num); |
| |
| // Override. This function is called for humongous allocation, so we need to find empty or unavailable regions in nv-dimm. |
| uint find_contiguous_empty_or_unavailable(size_t num); |
| |
| // Overrides base class implementation to find highest free region in dram. |
| uint find_highest_free(bool* expanded); |
| |
| // Override. This fuction is called to shrink the heap, we shrink in dram first then in nv-dimm. |
| uint shrink_by(uint num_regions_to_remove); |
| |
| bool has_borrowed_regions() const; |
| |
| void verify(); |
| }; |
| |
| #endif // SHARE_GC_G1_HETEROGENEOUSHEAPREGIONMANAGER_HPP |