6896647: card marks can be deferred too long Summary: Deferred card marks are now flushed during the gc prologue. Parallel[Scavege,OldGC] and SerialGC no longer defer card marks generated by COMPILER2 as a result of ReduceInitialCardMarks. For these cases, introduced a diagnostic option to defer the card marks, only for the purposes of testing and diagnostics. CMS and G1 continue to defer card marks. Potential performance concern related to single-threaded flushing of deferred card marks in the gc prologue will be addressed in the future. Reviewed-by: never, johnc

--- a/src/share/vm/memory/genCollectedHeap.cpp	Tue Jan 12 14:56:46 2010 -0800
+++ b/src/share/vm/memory/genCollectedHeap.cpp	Wed Jan 13 15:26:39 2010 -0800
@@ -51,6 +51,8 @@
 }
 
 jint GenCollectedHeap::initialize() {
+  CollectedHeap::pre_initialize();
+
   int i;
   _n_gens = gen_policy()->number_of_generations();
 
@@ -129,6 +131,7 @@
 
   _rem_set = collector_policy()->create_rem_set(_reserved, n_covered_regions);
   set_barrier_set(rem_set()->bs());
+
   _gch = this;
 
   for (i = 0; i < _n_gens; i++) {