Fri, 10 Oct 2014 15:51:58 +0200
8059758: Footprint regressions with JDK-8038423
Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything.
Reviewed-by: jwilhelm, brutisso
1 /*
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25 #include "precompiled.hpp"
26 #include "gc_implementation/g1/g1HRPrinter.hpp"
27 #include "gc_implementation/g1/heapRegion.hpp"
28 #include "utilities/ostream.hpp"
30 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
32 const char* G1HRPrinter::action_name(ActionType action) {
33 switch(action) {
34 case Alloc: return "ALLOC";
35 case AllocForce: return "ALLOC-FORCE";
36 case Retire: return "RETIRE";
37 case Reuse: return "REUSE";
38 case CSet: return "CSET";
39 case EvacFailure: return "EVAC-FAILURE";
40 case Cleanup: return "CLEANUP";
41 case PostCompaction: return "POST-COMPACTION";
42 case Commit: return "COMMIT";
43 case Uncommit: return "UNCOMMIT";
44 default: ShouldNotReachHere();
45 }
46 // trying to keep the Windows compiler happy
47 return NULL;
48 }
50 const char* G1HRPrinter::region_type_name(RegionType type) {
51 switch (type) {
52 case Unset: return NULL;
53 case Eden: return "Eden";
54 case Survivor: return "Survivor";
55 case Old: return "Old";
56 case SingleHumongous: return "SingleH";
57 case StartsHumongous: return "StartsH";
58 case ContinuesHumongous: return "ContinuesH";
59 default: ShouldNotReachHere();
60 }
61 // trying to keep the Windows compiler happy
62 return NULL;
63 }
65 const char* G1HRPrinter::phase_name(PhaseType phase) {
66 switch (phase) {
67 case StartGC: return "StartGC";
68 case EndGC: return "EndGC";
69 case StartFullGC: return "StartFullGC";
70 case EndFullGC: return "EndFullGC";
71 default: ShouldNotReachHere();
72 }
73 // trying to keep the Windows compiler happy
74 return NULL;
75 }
77 #define G1HR_PREFIX " G1HR"
79 void G1HRPrinter::print(ActionType action, RegionType type,
80 HeapRegion* hr, HeapWord* top) {
81 const char* action_str = action_name(action);
82 const char* type_str = region_type_name(type);
83 HeapWord* bottom = hr->bottom();
85 if (type_str != NULL) {
86 if (top != NULL) {
87 gclog_or_tty->print_cr(G1HR_PREFIX" %s(%s) "PTR_FORMAT" "PTR_FORMAT,
88 action_str, type_str, bottom, top);
89 } else {
90 gclog_or_tty->print_cr(G1HR_PREFIX" %s(%s) "PTR_FORMAT,
91 action_str, type_str, bottom);
92 }
93 } else {
94 if (top != NULL) {
95 gclog_or_tty->print_cr(G1HR_PREFIX" %s "PTR_FORMAT" "PTR_FORMAT,
96 action_str, bottom, top);
97 } else {
98 gclog_or_tty->print_cr(G1HR_PREFIX" %s "PTR_FORMAT,
99 action_str, bottom);
100 }
101 }
102 }
104 void G1HRPrinter::print(ActionType action, HeapWord* bottom, HeapWord* end) {
105 const char* action_str = action_name(action);
107 gclog_or_tty->print_cr(G1HR_PREFIX" %s ["PTR_FORMAT","PTR_FORMAT"]",
108 action_str, bottom, end);
109 }
111 void G1HRPrinter::print(PhaseType phase, size_t phase_num) {
112 const char* phase_str = phase_name(phase);
113 gclog_or_tty->print_cr(G1HR_PREFIX" #%s "SIZE_FORMAT, phase_str, phase_num);
114 }