src/share/vm/gc_implementation/g1/g1_globals.hpp

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rev 4561 : 7176479: G1: JVM crashes on T5-8 system with 1.5 TB heap
Summary: Refactor G1's hot card cache and card counts table into their own files. Simplify the card counts table, including removing the encoding of the card index in each entry. The card counts table now has a 1:1 correspondence with the cards spanned by heap. Space for the card counts table is reserved from virtual memory (rather than C heap) during JVM startup and is committed/expanded when the heap is expanded. Changes were also reviewed-by Vitaly Davidovich.
Reviewed-by:

@@ -161,20 +161,16 @@
                                                                             \
   product(bool, G1UseAdaptiveConcRefinement, true,                          \
           "Select green, yellow and red zones adaptively to meet the "      \
           "the pause requirements.")                                        \
                                                                             \
-  develop(intx, G1ConcRSLogCacheSize, 10,                                   \
+  product(uintx, G1ConcRSLogCacheSize, 10,                                  \
           "Log base 2 of the length of conc RS hot-card cache.")            \
                                                                             \
-  develop(intx, G1ConcRSHotCardLimit, 4,                                    \
+  product(uintx, G1ConcRSHotCardLimit, 4,                                   \
           "The threshold that defines (>=) a hot card.")                    \
                                                                             \
-  develop(intx, G1MaxHotCardCountSizePercent, 25,                           \
-          "The maximum size of the hot card count cache as a "              \
-          "percentage of the number of cards for the maximum heap.")        \
-                                                                            \
   develop(bool, G1PrintOopAppls, false,                                     \
           "When true, print applications of closures to external locs.")    \
                                                                             \
   develop(intx, G1RSetRegionEntriesBase, 256,                               \
           "Max number of regions in a fine-grain table per MB.")            \

@@ -245,14 +241,10 @@
                                                                             \
   product(uintx, G1ConcRefinementThreads, 0,                                \
           "If non-0 is the number of parallel rem set update threads, "     \
           "otherwise the value is determined ergonomically.")               \
                                                                             \
-  develop(intx, G1CardCountCacheExpandThreshold, 16,                        \
-          "Expand the card count cache if the number of collisions for "    \
-          "a particular entry exceeds this value.")                         \
-                                                                            \
   develop(bool, G1VerifyCTCleanup, false,                                   \
           "Verify card table cleanup.")                                     \
                                                                             \
   product(uintx, G1RSetScanBlockSize, 64,                                   \
           "Size of a work unit of cards claimed by a worker thread"         \