20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP
26 #define SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP
27
28 #include "gc/shared/gcUtil.hpp"
29 #include "oops/typeArrayOop.hpp"
30 #include "runtime/perfData.hpp"
31 #include "runtime/vm_version.hpp"
32
33 class GlobalTLABStats;
34
35 // ThreadLocalAllocBuffer: a descriptor for thread-local storage used by
36 // the threads for allocation.
37 // It is thread-private at any time, but maybe multiplexed over
38 // time across multiple threads. The park()/unpark() pair is
39 // used to make it available for such multiplexing.
40 class ThreadLocalAllocBuffer: public CHeapObj<mtThread> {
41 friend class VMStructs;
42 friend class JVMCIVMStructs;
43 private:
44 HeapWord* _start; // address of TLAB
45 HeapWord* _top; // address after last allocation
46 HeapWord* _pf_top; // allocation prefetch watermark
47 HeapWord* _end; // allocation end (excluding alignment_reserve)
48 size_t _desired_size; // desired size (including alignment_reserve)
49 size_t _refill_waste_limit; // hold onto tlab if free() is larger than this
50 size_t _allocated_before_last_gc; // total bytes allocated up until the last gc
51
52 static size_t _max_size; // maximum size of any TLAB
53 static int _reserve_for_allocation_prefetch; // Reserve at the end of the TLAB
54 static unsigned _target_refills; // expected number of refills between GCs
55
56 unsigned _number_of_refills;
57 unsigned _fast_refill_waste;
58 unsigned _slow_refill_waste;
59 unsigned _gc_waste;
60 unsigned _slow_allocations;
61
62 AdaptiveWeightedAverage _allocation_fraction; // fraction of eden allocated in tlabs
63
64 void accumulate_statistics();
65 void initialize_statistics();
66
67 void set_start(HeapWord* start) { _start = start; }
68 void set_end(HeapWord* end) { _end = end; }
69 void set_top(HeapWord* top) { _top = top; }
70 void set_pf_top(HeapWord* pf_top) { _pf_top = pf_top; }
71 void set_desired_size(size_t desired_size) { _desired_size = desired_size; }
72 void set_refill_waste_limit(size_t waste) { _refill_waste_limit = waste; }
73
74 size_t initial_refill_waste_limit() { return desired_size() / TLABRefillWasteFraction; }
75
76 static int target_refills() { return _target_refills; }
77 size_t initial_desired_size();
78
79 size_t remaining() const { return end() == NULL ? 0 : pointer_delta(hard_end(), top()); }
80
81 // Make parsable and release it.
82 void reset();
83
84 // Resize based on amount of allocation, etc.
85 void resize();
86
87 void invariants() const { assert(top() >= start() && top() <= end(), "invalid tlab"); }
88
89 void initialize(HeapWord* start, HeapWord* top, HeapWord* end);
90
91 void print_stats(const char* tag);
92
93 Thread* myThread();
94
95 // statistics
96
97 int number_of_refills() const { return _number_of_refills; }
98 int fast_refill_waste() const { return _fast_refill_waste; }
99 int slow_refill_waste() const { return _slow_refill_waste; }
100 int gc_waste() const { return _gc_waste; }
101 int slow_allocations() const { return _slow_allocations; }
102
103 static GlobalTLABStats* _global_stats;
104 static GlobalTLABStats* global_stats() { return _global_stats; }
105
106 public:
107 ThreadLocalAllocBuffer() : _allocation_fraction(TLABAllocationWeight), _allocated_before_last_gc(0) {
108 // do nothing. tlabs must be inited by initialize() calls
109 }
110
111 static size_t min_size() { return align_object_size(MinTLABSize / HeapWordSize) + alignment_reserve(); }
112 static size_t max_size() { assert(_max_size != 0, "max_size not set up"); return _max_size; }
113 static size_t max_size_in_bytes() { return max_size() * BytesPerWord; }
114 static void set_max_size(size_t max_size) { _max_size = max_size; }
115
116 HeapWord* start() const { return _start; }
117 HeapWord* end() const { return _end; }
118 HeapWord* hard_end() const { return _end + alignment_reserve(); }
119 HeapWord* top() const { return _top; }
120 HeapWord* pf_top() const { return _pf_top; }
121 size_t desired_size() const { return _desired_size; }
122 size_t used() const { return pointer_delta(top(), start()); }
123 size_t used_bytes() const { return pointer_delta(top(), start(), 1); }
124 size_t free() const { return pointer_delta(end(), top()); }
125 // Don't discard tlab if remaining space is larger than this.
126 size_t refill_waste_limit() const { return _refill_waste_limit; }
127
128 // Allocate size HeapWords. The memory is NOT initialized to zero.
129 inline HeapWord* allocate(size_t size);
130
131 // Reserve space at the end of TLAB
132 static size_t end_reserve() {
133 int reserve_size = typeArrayOopDesc::header_size(T_INT);
134 return MAX2(reserve_size, _reserve_for_allocation_prefetch);
135 }
136 static size_t alignment_reserve() { return align_object_size(end_reserve()); }
137 static size_t alignment_reserve_in_bytes() { return alignment_reserve() * HeapWordSize; }
138
139 // Return tlab size or remaining space in eden such that the
140 // space is large enough to hold obj_size and necessary fill space.
141 // Otherwise return 0;
142 inline size_t compute_size(size_t obj_size);
143
144 // Record slow allocation
145 inline void record_slow_allocation(size_t obj_size);
146
147 // Initialization at startup
148 static void startup_initialization();
149
150 // Make an in-use tlab parsable, optionally retiring and/or zapping it.
151 void make_parsable(bool retire, bool zap = true);
152
153 // Retire in-use tlab before allocation of a new tlab
154 void clear_before_allocation();
155
156 // Accumulate statistics across all tlabs before gc
157 static void accumulate_statistics_before_gc();
158
159 // Resize tlabs for all threads
160 static void resize_all_tlabs();
161
162 void fill(HeapWord* start, HeapWord* top, size_t new_size);
163 void initialize();
164
165 static size_t refill_waste_limit_increment() { return TLABWasteIncrement; }
166
167 // Code generation support
168 static ByteSize start_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _start); }
169 static ByteSize end_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _end ); }
170 static ByteSize top_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _top ); }
171 static ByteSize pf_top_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _pf_top ); }
172 static ByteSize size_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _desired_size ); }
173 static ByteSize refill_waste_limit_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _refill_waste_limit ); }
174
175 static ByteSize number_of_refills_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _number_of_refills ); }
176 static ByteSize fast_refill_waste_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _fast_refill_waste ); }
177 static ByteSize slow_allocations_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _slow_allocations ); }
178
179 void verify();
180 };
181
182 class GlobalTLABStats: public CHeapObj<mtThread> {
183 private:
184
185 // Accumulate perfdata in private variables because
186 // PerfData should be write-only for security reasons
187 // (see perfData.hpp)
188 unsigned _allocating_threads;
189 unsigned _total_refills;
|
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP
26 #define SHARE_VM_GC_SHARED_THREADLOCALALLOCBUFFER_HPP
27
28 #include "gc/shared/gcUtil.hpp"
29 #include "oops/typeArrayOop.hpp"
30 #include "runtime/perfData.hpp"
31 #include "runtime/vm_version.hpp"
32
33 class GlobalTLABStats;
34
35 // ThreadLocalAllocBuffer: a descriptor for thread-local storage used by
36 // the threads for allocation.
37 // It is thread-private at any time, but maybe multiplexed over
38 // time across multiple threads. The park()/unpark() pair is
39 // used to make it available for such multiplexing.
40 //
41 // Heap sampling is performed via the current_end/allocation_end
42 // fields.
43 // allocation_end contains the real end of the tlab allocation,
44 // whereas current_end can be set to an arbitrary spot in the tlab to
45 // trip the return and sample the allocation.
46 class ThreadLocalAllocBuffer: public CHeapObj<mtThread> {
47 friend class VMStructs;
48 friend class JVMCIVMStructs;
49 private:
50 HeapWord* _start; // address of TLAB
51 HeapWord* _top; // address after last allocation
52 HeapWord* _pf_top; // allocation prefetch watermark
53 HeapWord* _current_end; // allocation end (can be the sampling end point or _allocation_end)
54 HeapWord* _allocation_end; // end for allocations (actual TLAB end, excluding alignment_reserve)
55
56 size_t _desired_size; // desired size (including alignment_reserve)
57 size_t _refill_waste_limit; // hold onto tlab if free() is larger than this
58 size_t _allocated_before_last_gc; // total bytes allocated up until the last gc
59 size_t _bytes_since_last_sample_point; // bytes since last sample point.
60
61 static size_t _max_size; // maximum size of any TLAB
62 static int _reserve_for_allocation_prefetch; // Reserve at the end of the TLAB
63 static unsigned _target_refills; // expected number of refills between GCs
64
65 unsigned _number_of_refills;
66 unsigned _fast_refill_waste;
67 unsigned _slow_refill_waste;
68 unsigned _gc_waste;
69 unsigned _slow_allocations;
70
71 AdaptiveWeightedAverage _allocation_fraction; // fraction of eden allocated in tlabs
72
73 void accumulate_statistics();
74 void initialize_statistics();
75
76 void set_start(HeapWord* start) { _start = start; }
77 void set_current_end(HeapWord* current_end) { _current_end = current_end; }
78 void set_allocation_end(HeapWord* ptr) { _allocation_end = ptr; }
79 void set_top(HeapWord* top) { _top = top; }
80 void set_pf_top(HeapWord* pf_top) { _pf_top = pf_top; }
81 void set_desired_size(size_t desired_size) { _desired_size = desired_size; }
82 void set_refill_waste_limit(size_t waste) { _refill_waste_limit = waste; }
83
84 size_t initial_refill_waste_limit() { return desired_size() / TLABRefillWasteFraction; }
85
86 static int target_refills() { return _target_refills; }
87 size_t initial_desired_size();
88
89 size_t remaining();
90
91 void update_end_pointers();
92
93 // Make parsable and release it.
94 void reset();
95
96 // Resize based on amount of allocation, etc.
97 void resize();
98
99 void invariants() const { assert(top() >= start() && top() <= current_end(), "invalid tlab"); }
100
101 void initialize(HeapWord* start, HeapWord* top, HeapWord* end);
102
103 void print_stats(const char* tag);
104
105 Thread* myThread();
106
107 // statistics
108
109 int number_of_refills() const { return _number_of_refills; }
110 int fast_refill_waste() const { return _fast_refill_waste; }
111 int slow_refill_waste() const { return _slow_refill_waste; }
112 int gc_waste() const { return _gc_waste; }
113 int slow_allocations() const { return _slow_allocations; }
114
115 static GlobalTLABStats* _global_stats;
116 static GlobalTLABStats* global_stats() { return _global_stats; }
117
118 public:
119 ThreadLocalAllocBuffer() : _allocation_fraction(TLABAllocationWeight), _allocated_before_last_gc(0) {
120 // do nothing. tlabs must be inited by initialize() calls
121 }
122
123 static size_t min_size() { return align_object_size(MinTLABSize / HeapWordSize) + alignment_reserve(); }
124 static size_t max_size() { assert(_max_size != 0, "max_size not set up"); return _max_size; }
125 static size_t max_size_in_bytes() { return max_size() * BytesPerWord; }
126 static void set_max_size(size_t max_size) { _max_size = max_size; }
127
128 HeapWord* start() const { return _start; }
129 HeapWord* current_end() const { return _current_end; }
130 HeapWord* top() const { return _top; }
131 HeapWord* reserved_end();
132 HeapWord* pf_top() const { return _pf_top; }
133 size_t desired_size() const { return _desired_size; }
134 size_t used() const { return pointer_delta(top(), start()); }
135 size_t used_bytes() const { return pointer_delta(top(), start(), 1); }
136 size_t free() const { return pointer_delta(current_end(), top()); }
137 // Don't discard tlab if remaining space is larger than this.
138 size_t refill_waste_limit() const { return _refill_waste_limit; }
139 size_t bytes_since_last_sample_point() const { return _bytes_since_last_sample_point; }
140
141 // Allocate size HeapWords. The memory is NOT initialized to zero.
142 inline HeapWord* allocate(size_t size);
143 HeapWord* allocate_sampled_object(size_t size);
144
145 // Reserve space at the end of TLAB
146 static size_t end_reserve() {
147 int reserve_size = typeArrayOopDesc::header_size(T_INT);
148 return MAX2(reserve_size, _reserve_for_allocation_prefetch);
149 }
150 static size_t alignment_reserve() { return align_object_size(end_reserve()); }
151 static size_t alignment_reserve_in_bytes() { return alignment_reserve() * HeapWordSize; }
152
153 // Return tlab size or remaining space in eden such that the
154 // space is large enough to hold obj_size and necessary fill space.
155 // Otherwise return 0;
156 inline size_t compute_size(size_t obj_size);
157
158 // Record slow allocation
159 inline void record_slow_allocation(size_t obj_size);
160
161 // Initialization at startup
162 static void startup_initialization();
163
164 // Make an in-use tlab parsable, optionally retiring and/or zapping it.
165 void make_parsable(bool retire, bool zap = true);
166
167 // Retire in-use tlab before allocation of a new tlab
168 void clear_before_allocation();
169
170 // Accumulate statistics across all tlabs before gc
171 static void accumulate_statistics_before_gc();
172
173 // Resize tlabs for all threads
174 static void resize_all_tlabs();
175
176 void fill(HeapWord* start, HeapWord* top, size_t new_size);
177 void initialize();
178
179 void set_back_allocation_end();
180 void set_sample_end();
181
182 static size_t refill_waste_limit_increment() { return TLABWasteIncrement; }
183
184 // Code generation support
185 static ByteSize start_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _start); }
186 static ByteSize current_end_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _current_end ); }
187 static ByteSize top_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _top ); }
188 static ByteSize pf_top_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _pf_top ); }
189 static ByteSize size_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _desired_size ); }
190 static ByteSize refill_waste_limit_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _refill_waste_limit ); }
191
192 static ByteSize number_of_refills_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _number_of_refills ); }
193 static ByteSize fast_refill_waste_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _fast_refill_waste ); }
194 static ByteSize slow_allocations_offset() { return byte_offset_of(ThreadLocalAllocBuffer, _slow_allocations ); }
195
196 void verify();
197 };
198
199 class GlobalTLABStats: public CHeapObj<mtThread> {
200 private:
201
202 // Accumulate perfdata in private variables because
203 // PerfData should be write-only for security reasons
204 // (see perfData.hpp)
205 unsigned _allocating_threads;
206 unsigned _total_refills;
|