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_G1_G1CONCURRENTREFINE_HPP
26 #define SHARE_VM_GC_G1_G1CONCURRENTREFINE_HPP
27
28 #include "memory/allocation.hpp"
29 #include "utilities/globalDefinitions.hpp"
30
31 // Forward decl
32 class CardTableEntryClosure;
33 class G1ConcurrentRefineThread;
34 class outputStream;
35 class ThreadClosure;
36
37 class G1ConcurrentRefine : public CHeapObj<mtGC> {
38 G1ConcurrentRefineThread** _threads;
39 uint _n_worker_threads;
40 /*
41 * The value of the update buffer queue length falls into one of 3 zones:
42 * green, yellow, red. If the value is in [0, green) nothing is
43 * done, the buffers are left unprocessed to enable the caching effect of the
44 * dirtied cards. In the yellow zone [green, yellow) the concurrent refinement
45 * threads are gradually activated. In [yellow, red) all threads are
46 * running. If the length becomes red (max queue length) the mutators start
47 * processing the buffers.
48 *
49 * There are some interesting cases (when G1UseAdaptiveConcRefinement
50 * is turned off):
51 * 1) green = yellow = red = 0. In this case the mutator will process all
52 * buffers. Except for those that are created by the deferred updates
53 * machinery during a collection.
54 * 2) green = 0. Means no caching. Can be a good way to minimize the
55 * amount of time spent updating rsets during a collection.
56 */
57 size_t _green_zone;
58 size_t _yellow_zone;
59 size_t _red_zone;
60 size_t _min_yellow_zone_size;
61
62 G1ConcurrentRefine(size_t green_zone,
63 size_t yellow_zone,
64 size_t red_zone,
65 size_t min_yellow_zone_size);
66
67 // Update green/yellow/red zone values based on how well goals are being met.
68 void update_zones(double update_rs_time,
69 size_t update_rs_processed_buffers,
70 double goal_ms);
71
72 // Update thread thresholds to account for updated zone values.
73 void update_thread_thresholds();
74
75 public:
76 ~G1ConcurrentRefine();
77
78 // Returns a G1ConcurrentRefine instance if succeeded to create/initialize G1ConcurrentRefine and G1ConcurrentRefineThreads.
79 // Otherwise, returns NULL with error code.
80 static G1ConcurrentRefine* create(jint* ecode);
81
82 void stop();
83
84 void adjust(double update_rs_time, size_t update_rs_processed_buffers, double goal_ms);
85
86 // Iterate over all concurrent refinement threads applying the given closure.
87 void threads_do(ThreadClosure *tc);
88
89 static uint thread_num();
90
91 void print_threads_on(outputStream* st) const;
92
93 size_t green_zone() const { return _green_zone; }
94 size_t yellow_zone() const { return _yellow_zone; }
95 size_t red_zone() const { return _red_zone; }
96 };
97
98 #endif // SHARE_VM_GC_G1_G1CONCURRENTREFINE_HPP
|
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_G1_G1CONCURRENTREFINE_HPP
26 #define SHARE_VM_GC_G1_G1CONCURRENTREFINE_HPP
27
28 #include "memory/allocation.hpp"
29 #include "utilities/globalDefinitions.hpp"
30
31 // Forward decl
32 class CardTableEntryClosure;
33 class G1ConcurrentRefine;
34 class G1ConcurrentRefineThread;
35 class outputStream;
36 class ThreadClosure;
37
38 // Helper class for refinement thread management. Used to start, stop and
39 // iterate over them.
40 class G1ConcurrentRefineThreadControl VALUE_OBJ_CLASS_SPEC {
41 G1ConcurrentRefine* _cr;
42
43 G1ConcurrentRefineThread** _threads;
44 uint _num_max_threads;
45
46 // Create the refinement thread for the given worker id.
47 // If initializing is true, ignore InjectGCWorkerCreationFailure.
48 G1ConcurrentRefineThread* create_refinement_thread(uint worker_id, bool initializing);
49 public:
50 G1ConcurrentRefineThreadControl();
51 ~G1ConcurrentRefineThreadControl();
52
53 jint initialize(G1ConcurrentRefine* cr, uint num_max_threads);
54
55 // If there is a "successor" thread that can be activated given the current id,
56 // activate it.
57 void maybe_activate_next(uint cur_worker_id);
58
59 void print_on(outputStream* st) const;
60 void worker_threads_do(ThreadClosure* tc);
61 void stop();
62 };
63
64 // Controls refinement threads and their activation based on the number of completed
65 // buffers currently available in the global dirty card queue.
66 // Refinement threads pick work from the queue based on these thresholds. They are activated
67 // gradually based on the amount of work to do.
68 // Refinement thread n activates thread n+1 if the instance of this class determines there
69 // is enough work available. Threads deactivate themselves if the current amount of
70 // completed buffers falls below their individual threshold.
71 class G1ConcurrentRefine : public CHeapObj<mtGC> {
72 G1ConcurrentRefineThreadControl _thread_control;
73 /*
74 * The value of the completed dirty card queue length falls into one of 3 zones:
75 * green, yellow, red. If the value is in [0, green) nothing is
76 * done, the buffers are left unprocessed to enable the caching effect of the
77 * dirtied cards. In the yellow zone [green, yellow) the concurrent refinement
78 * threads are gradually activated. In [yellow, red) all threads are
79 * running. If the length becomes red (max queue length) the mutators start
80 * processing the buffers.
81 *
82 * There are some interesting cases (when G1UseAdaptiveConcRefinement
83 * is turned off):
84 * 1) green = yellow = red = 0. In this case the mutator will process all
85 * buffers. Except for those that are created by the deferred updates
86 * machinery during a collection.
87 * 2) green = 0. Means no caching. Can be a good way to minimize the
88 * amount of time spent updating remembered sets during a collection.
89 */
90 size_t _green_zone;
91 size_t _yellow_zone;
92 size_t _red_zone;
93 size_t _min_yellow_zone_size;
94
95 G1ConcurrentRefine(size_t green_zone,
96 size_t yellow_zone,
97 size_t red_zone,
98 size_t min_yellow_zone_size);
99
100 // Update green/yellow/red zone values based on how well goals are being met.
101 void update_zones(double update_rs_time,
102 size_t update_rs_processed_buffers,
103 double goal_ms);
104
105 static uint worker_id_offset();
106 void maybe_activate_more_threads(uint worker_id, size_t num_cur_buffers);
107
108 jint initialize();
109 public:
110 ~G1ConcurrentRefine();
111
112 // Returns a G1ConcurrentRefine instance if succeeded to create/initialize the
113 // G1ConcurrentRefine instance. Otherwise, returns NULL with error code.
114 static G1ConcurrentRefine* create(jint* ecode);
115
116 void stop();
117
118 // Adjust refinement thresholds based on work done during the pause and the goal time.
119 void adjust(double update_rs_time, size_t update_rs_processed_buffers, double goal_ms);
120
121 size_t activation_threshold(uint worker_id) const;
122 size_t deactivation_threshold(uint worker_id) const;
123 // Perform a single refinement step. Called by the refinement threads when woken up.
124 bool do_refinement_step(uint worker_id);
125
126 // Iterate over all concurrent refinement threads applying the given closure.
127 void threads_do(ThreadClosure *tc);
128
129 // Maximum number of refinement threads.
130 static uint max_num_threads();
131
132 void print_threads_on(outputStream* st) const;
133
134 size_t green_zone() const { return _green_zone; }
135 size_t yellow_zone() const { return _yellow_zone; }
136 size_t red_zone() const { return _red_zone; }
137 };
138
139 #endif // SHARE_VM_GC_G1_G1CONCURRENTREFINE_HPP
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