Summary: G1 now answers "no" to the query can_elide_initializing_store_barrier() in the product build. A debug flag allows alternate behaviour in debug builds.
Reviewed-by: iveresov, tonyp

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

Summary: G1 reports committed memory instead of reserved memory from the Runtime.maxMemory() method
Reviewed-by: ysr, jmasa

6889757: G1: enable card mark elision for initializing writes from compiled code (ReduceInitialCardMarks)
Summary: Defer the (compiler-elided) card-mark upon a slow-path allocation until after the store  and before the next subsequent safepoint; G1 now answers yes to can_elide_tlab_write_barriers().
Reviewed-by: jcoomes, kvn, never

Summary: Instead of the region size being hard-coded, allow the user to set it.
Reviewed-by: jmasa, johnc, apetrusenko

Summary: Treat ProfileData in MDO's as a source of weak, not strong, roots. Fixes the bug for stop-world collection -- the case of concurrent collection will be fixed separately.
Reviewed-by: jcoomes, jmasa, kvn, never

Summary: The used() method assumes that the heap lock is held when it is called. However, when used() is called from print_on(), this is not the case.
Reviewed-by: ysr, jmasa

Summary: Modifications to G1 so as to allow the use of compressed oops.
Reviewed-by: apetrusenko, coleenp, jmasa, kvn, never, phh, tonyp

Summary: Changing the behavior of -XX:+PrintHeapAtGC for G1 from printing lengthy, per-region information to instead printing a concise summary.
Reviewed-by: ysr, apetrusenko, jcoomes

Summary: extend G1 marking verification to use either the "prev" or "next" marking information, as appropriate.
Reviewed-by: johnc, ysr

Summary: For heaps larger than 32Gb, the number of heap regions overflows the data type used to hold the region index in the SparsePRT structure. Changed the region indexes, card indexes, and RSet hash table buckets to ints and added some size overflow guarantees.
Reviewed-by: ysr, tonyp

Reviewed-by: iveresov, tonyp

Summary: Make object_iterate() traverse the perm gen
Reviewed-by: apetrusenko, tonyp

Reviewed-by: iveresov, tonyp

6728271: G1: Cleanup G1CollectedHeap::get_gc_alloc_regions()
Summary: It allows the last half-full region to be allocated to during a GC to be reused during the next GC.
Reviewed-by: apetrusenko, jcoomes

Summary: Update copyright for files that have been modified in 2009, up to 03/09
Reviewed-by: katleman, tbell, ohair

6720334: G1: don't update RSets of collection set regions during an evacuation pause
Summary: Introduced a deferred update mechanism for delaying the rset updates during the collection pause
Reviewed-by: apetrusenko, tonyp

6797754: G1: combined bugfix
Summary: Implemented a policy to control G1 survivor space parameters.
Reviewed-by: tonyp, iveresov

Summary: A bunch of performance optimizations to decrease GC pause times in G1.
Reviewed-by: apetrusenko, jmasa, iveresov

Summary: Added safe_object_iterate() for use by JMapPerm.
Reviewed-by: tonyp

Summary: Update copyright for files that have been modified starting July 2008 to Dec 2008
Reviewed-by: katleman, ohair, tbell

Summary: Introduce parallel heap verification in G1.
Reviewed-by: jcoomes, apetrusenko

Summary: Under certain circumstances, two cleanup threads can claim and process the same region.
Reviewed-by: apetrusenko, ysr

6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
Summary: Fixed the incorrect assigment to G1OffsetTableContigSpace::_gc_time_stamp. Also added a little more paranoia to operations on a global timestamp.
Reviewed-by: tonyp

Summary: First mercurial integration of the code for the Garbage-First garbage collector.
Reviewed-by: apetrusenko, iveresov, jmasa, sgoldman, tonyp, ysr