1/*
2 * Copyright (c) 2006, 2015, 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.
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23 */
24
25#ifndef SHARE_VM_GC_PARALLEL_MUTABLENUMASPACE_HPP
26#define SHARE_VM_GC_PARALLEL_MUTABLENUMASPACE_HPP
27
28#include "gc/parallel/mutableSpace.hpp"
29#include "gc/shared/gcUtil.hpp"
30#include "utilities/macros.hpp"
31
32/*
33 *    The NUMA-aware allocator (MutableNUMASpace) is basically a modification
34 * of MutableSpace which preserves interfaces but implements different
35 * functionality. The space is split into chunks for each locality group
36 * (resizing for adaptive size policy is also supported). For each thread
37 * allocations are performed in the chunk corresponding to the home locality
38 * group of the thread. Whenever any chunk fills-in the young generation
39 * collection occurs.
40 *   The chunks can be also be adaptively resized. The idea behind the adaptive
41 * sizing is to reduce the loss of the space in the eden due to fragmentation.
42 * The main cause of fragmentation is uneven allocation rates of threads.
43 * The allocation rate difference between locality groups may be caused either by
44 * application specifics or by uneven LWP distribution by the OS. Besides,
45 * application can have less threads then the number of locality groups.
46 * In order to resize the chunk we measure the allocation rate of the
47 * application between collections. After that we reshape the chunks to reflect
48 * the allocation rate pattern. The AdaptiveWeightedAverage exponentially
49 * decaying average is used to smooth the measurements. The NUMASpaceResizeRate
50 * parameter is used to control the adaptation speed by restricting the number of
51 * bytes that can be moved during the adaptation phase.
52 *   Chunks may contain pages from a wrong locality group. The page-scanner has
53 * been introduced to address the problem. Remote pages typically appear due to
54 * the memory shortage in the target locality group. Besides Solaris would
55 * allocate a large page from the remote locality group even if there are small
56 * local pages available. The page-scanner scans the pages right after the
57 * collection and frees remote pages in hope that subsequent reallocation would
58 * be more successful. This approach proved to be useful on systems with high
59 * load where multiple processes are competing for the memory.
60 */
61
62class MutableNUMASpace : public MutableSpace {
63  friend class VMStructs;
64
65  class LGRPSpace : public CHeapObj<mtGC> {
66    int _lgrp_id;
67    MutableSpace* _space;
68    MemRegion _invalid_region;
69    AdaptiveWeightedAverage *_alloc_rate;
70    bool _allocation_failed;
71
72    struct SpaceStats {
73      size_t _local_space, _remote_space, _unbiased_space, _uncommited_space;
74      size_t _large_pages, _small_pages;
75
76      SpaceStats() {
77        _local_space = 0;
78        _remote_space = 0;
79        _unbiased_space = 0;
80        _uncommited_space = 0;
81        _large_pages = 0;
82        _small_pages = 0;
83      }
84    };
85
86    SpaceStats _space_stats;
87
88    char* _last_page_scanned;
89    char* last_page_scanned()            { return _last_page_scanned; }
90    void set_last_page_scanned(char* p)  { _last_page_scanned = p;    }
91   public:
92    LGRPSpace(int l, size_t alignment) : _lgrp_id(l), _last_page_scanned(NULL), _allocation_failed(false) {
93      _space = new MutableSpace(alignment);
94      _alloc_rate = new AdaptiveWeightedAverage(NUMAChunkResizeWeight);
95    }
96    ~LGRPSpace() {
97      delete _space;
98      delete _alloc_rate;
99    }
100
101    void add_invalid_region(MemRegion r) {
102      if (!_invalid_region.is_empty()) {
103      _invalid_region.set_start(MIN2(_invalid_region.start(), r.start()));
104      _invalid_region.set_end(MAX2(_invalid_region.end(), r.end()));
105      } else {
106      _invalid_region = r;
107      }
108    }
109
110    static bool equals(void* lgrp_id_value, LGRPSpace* p) {
111      return *(int*)lgrp_id_value == p->lgrp_id();
112    }
113
114    // Report a failed allocation.
115    void set_allocation_failed() { _allocation_failed = true;  }
116
117    void sample() {
118      // If there was a failed allocation make allocation rate equal
119      // to the size of the whole chunk. This ensures the progress of
120      // the adaptation process.
121      size_t alloc_rate_sample;
122      if (_allocation_failed) {
123        alloc_rate_sample = space()->capacity_in_bytes();
124        _allocation_failed = false;
125      } else {
126        alloc_rate_sample = space()->used_in_bytes();
127      }
128      alloc_rate()->sample(alloc_rate_sample);
129    }
130
131    MemRegion invalid_region() const                { return _invalid_region;      }
132    void set_invalid_region(MemRegion r)            { _invalid_region = r;         }
133    int lgrp_id() const                             { return _lgrp_id;             }
134    MutableSpace* space() const                     { return _space;               }
135    AdaptiveWeightedAverage* alloc_rate() const     { return _alloc_rate;          }
136    void clear_alloc_rate()                         { _alloc_rate->clear();        }
137    SpaceStats* space_stats()                       { return &_space_stats;        }
138    void clear_space_stats()                        { _space_stats = SpaceStats(); }
139
140    void accumulate_statistics(size_t page_size);
141    void scan_pages(size_t page_size, size_t page_count);
142  };
143
144  GrowableArray<LGRPSpace*>* _lgrp_spaces;
145  size_t _page_size;
146  unsigned _adaptation_cycles, _samples_count;
147
148  void set_page_size(size_t psz)                     { _page_size = psz;          }
149  size_t page_size() const                           { return _page_size;         }
150
151  unsigned adaptation_cycles()                       { return _adaptation_cycles; }
152  void set_adaptation_cycles(int v)                  { _adaptation_cycles = v;    }
153
154  unsigned samples_count()                           { return _samples_count;     }
155  void increment_samples_count()                     { ++_samples_count;          }
156
157  size_t _base_space_size;
158  void set_base_space_size(size_t v)                 { _base_space_size = v;      }
159  size_t base_space_size() const                     { return _base_space_size;   }
160
161  // Check if the NUMA topology has changed. Add and remove spaces if needed.
162  // The update can be forced by setting the force parameter equal to true.
163  bool update_layout(bool force);
164  // Bias region towards the lgrp.
165  void bias_region(MemRegion mr, int lgrp_id);
166  // Free pages in a given region.
167  void free_region(MemRegion mr);
168  // Get current chunk size.
169  size_t current_chunk_size(int i);
170  // Get default chunk size (equally divide the space).
171  size_t default_chunk_size();
172  // Adapt the chunk size to follow the allocation rate.
173  size_t adaptive_chunk_size(int i, size_t limit);
174  // Scan and free invalid pages.
175  void scan_pages(size_t page_count);
176  // Return the bottom_region and the top_region. Align them to page_size() boundary.
177  // |------------------new_region---------------------------------|
178  // |----bottom_region--|---intersection---|------top_region------|
179  void select_tails(MemRegion new_region, MemRegion intersection,
180                    MemRegion* bottom_region, MemRegion *top_region);
181  // Try to merge the invalid region with the bottom or top region by decreasing
182  // the intersection area. Return the invalid_region aligned to the page_size()
183  // boundary if it's inside the intersection. Return non-empty invalid_region
184  // if it lies inside the intersection (also page-aligned).
185  // |------------------new_region---------------------------------|
186  // |----------------|-------invalid---|--------------------------|
187  // |----bottom_region--|---intersection---|------top_region------|
188  void merge_regions(MemRegion new_region, MemRegion* intersection,
189                     MemRegion *invalid_region);
190
191 public:
192  GrowableArray<LGRPSpace*>* lgrp_spaces() const     { return _lgrp_spaces;       }
193  MutableNUMASpace(size_t alignment);
194  virtual ~MutableNUMASpace();
195  // Space initialization.
196  virtual void initialize(MemRegion mr, bool clear_space, bool mangle_space, bool setup_pages = SetupPages);
197  // Update space layout if necessary. Do all adaptive resizing job.
198  virtual void update();
199  // Update allocation rate averages.
200  virtual void accumulate_statistics();
201
202  virtual void clear(bool mangle_space);
203  virtual void mangle_unused_area() PRODUCT_RETURN;
204  virtual void mangle_unused_area_complete() PRODUCT_RETURN;
205  virtual void mangle_region(MemRegion mr) PRODUCT_RETURN;
206  virtual void check_mangled_unused_area(HeapWord* limit) PRODUCT_RETURN;
207  virtual void check_mangled_unused_area_complete() PRODUCT_RETURN;
208  virtual void set_top_for_allocations(HeapWord* v) PRODUCT_RETURN;
209  virtual void set_top_for_allocations() PRODUCT_RETURN;
210
211  virtual void ensure_parsability();
212  virtual size_t used_in_words() const;
213  virtual size_t free_in_words() const;
214
215  using MutableSpace::capacity_in_words;
216  virtual size_t capacity_in_words(Thread* thr) const;
217  virtual size_t tlab_capacity(Thread* thr) const;
218  virtual size_t tlab_used(Thread* thr) const;
219  virtual size_t unsafe_max_tlab_alloc(Thread* thr) const;
220
221  // Allocation (return NULL if full)
222  virtual HeapWord* allocate(size_t word_size);
223  virtual HeapWord* cas_allocate(size_t word_size);
224
225  // Debugging
226  virtual void print_on(outputStream* st) const;
227  virtual void print_short_on(outputStream* st) const;
228  virtual void verify();
229
230  virtual void set_top(HeapWord* value);
231};
232
233#endif // SHARE_VM_GC_PARALLEL_MUTABLENUMASPACE_HPP
234