jdk-sandbox: comparison hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.hpp

equal deleted inserted replaced

-:917d8673b5ef
+:7dc5c8f572b0
 public MainBodySummary {
 public:
 virtual MainBodySummary*    main_body_summary()    { return this; }
 };
+// There are three command line options related to the young gen size:
+// NewSize, MaxNewSize and NewRatio (There is also -Xmn, but that is
+// just a short form for NewSize==MaxNewSize). G1 will use its internal
+// heuristics to calculate the actual young gen size, so these options
+// basically only limit the range within which G1 can pick a young gen
+// size. Also, these are general options taking byte sizes. G1 will
+// internally work with a number of regions instead. So, some rounding
+// will occur.
+//
+// If nothing related to the the young gen size is set on the command
+// line we should allow the young gen to be between
+// G1DefaultMinNewGenPercent and G1DefaultMaxNewGenPercent of the
+// heap size. This means that every time the heap size changes the
+// limits for the young gen size will be updated.
+//
+// If only -XX:NewSize is set we should use the specified value as the
+// minimum size for young gen. Still using G1DefaultMaxNewGenPercent
+// of the heap as maximum.
+//
+// If only -XX:MaxNewSize is set we should use the specified value as the
+// maximum size for young gen. Still using G1DefaultMinNewGenPercent
+// of the heap as minimum.
+//
+// If -XX:NewSize and -XX:MaxNewSize are both specified we use these values.
+// No updates when the heap size changes. There is a special case when
+// NewSize==MaxNewSize. This is interpreted as "fixed" and will use a
+// different heuristic for calculating the collection set when we do mixed
+// collection.
+//
+// If only -XX:NewRatio is set we should use the specified ratio of the heap
+// as both min and max. This will be interpreted as "fixed" just like the
+// NewSize==MaxNewSize case above. But we will update the min and max
+// everytime the heap size changes.
+//
+// NewSize and MaxNewSize override NewRatio. So, NewRatio is ignored if it is
+// combined with either NewSize or MaxNewSize. (A warning message is printed.)
+class G1YoungGenSizer : public CHeapObj {
+private:
+enum SizerKind {
+SizerDefaults,
+SizerNewSizeOnly,
+SizerMaxNewSizeOnly,
+SizerMaxAndNewSize,
+SizerNewRatio
+};
+SizerKind _sizer_kind;
+size_t _min_desired_young_length;
+size_t _max_desired_young_length;
+bool _adaptive_size;
+size_t calculate_default_min_length(size_t new_number_of_heap_regions);
+size_t calculate_default_max_length(size_t new_number_of_heap_regions);
+public:
+G1YoungGenSizer();
+void heap_size_changed(size_t new_number_of_heap_regions);
+size_t min_desired_young_length() {
+return _min_desired_young_length;
+}
+size_t max_desired_young_length() {
+return _max_desired_young_length;
+}
+bool adaptive_young_list_length() {
+return _adaptive_size;
+}
+};
 class G1CollectorPolicy: public CollectorPolicy {
 private:
 // either equal to the number of parallel threads, if ParallelGCThreads
 // has been set, or 1 otherwise
 int _parallel_gc_threads;
 double* _par_last_gc_worker_other_times_ms;
 // indicates whether we are in young or mixed GC mode
 bool _gcs_are_young;
-// if true, then it tries to dynamically adjust the length of the
-// young list
-bool _adaptive_young_list_length;
 size_t _young_list_target_length;
 size_t _young_list_fixed_length;
 size_t _prev_eden_capacity; // used for logging
 // The max number of regions we can extend the eden by while the GC
 TruncatedSeq* _cost_per_byte_ms_during_cm_seq;
 TruncatedSeq* _young_gc_eff_seq;
-bool   _using_new_ratio_calculations;
+G1YoungGenSizer* _young_gen_sizer;
-size_t _min_desired_young_length; // as set on the command line or default calculations
-size_t _max_desired_young_length; // as set on the command line or default calculations
 size_t _eden_cset_region_length;
 size_t _survivor_cset_region_length;
 size_t _old_cset_region_length;
 size_t base_free_regions, double target_pause_time_ms);
 // Count the number of bytes used in the CS.
 void count_CS_bytes_used();
-void update_young_list_size_using_newratio(size_t number_of_heap_regions);
 public:
 G1CollectorPolicy();
 virtual G1CollectorPolicy* as_g1_policy() { return this; }
 return _all_pause_times_ms->num() + 1;
 }
 // This should be called after the heap is resized.
 void record_new_heap_size(size_t new_number_of_regions);
-public:
 void init();
 // Create jstat counters for the policy.
 virtual void initialize_gc_policy_counters();
 void set_gcs_are_young(bool gcs_are_young) {
 _gcs_are_young = gcs_are_young;
 }
 bool adaptive_young_list_length() {
-return _adaptive_young_list_length;
+return _young_gen_sizer->adaptive_young_list_length();
-}
-void set_adaptive_young_list_length(bool adaptive_young_list_length) {
-_adaptive_young_list_length = adaptive_young_list_length;
 }
 inline double get_gc_eff_factor() {
 double ratio = _known_garbage_ratio;

changeset 11397	7dc5c8f572b0
parent 11395	33260c27554b
child 11455	a6ab3d8b9a4c