Reviewed-by: stefank, coleenp, kvn

Summary: Reset the fields in ParGCAllocBuffer, that are used for accumulating values for the ResizePLAB sensors in PLABStats, to zero after flushing the values to the PLABStats fields. Flush PLABStats values only when retiring the final allocation buffers prior to disposing of a G1ParScanThreadState object, rather than when retiring every allocation buffer.
Reviewed-by: jwilhelm, jmasa, ysr

Summary: The warnings associated with the UseMemSetInBOT flag are duplicated in CMS and G1. The separate warnings have been removed and single instance of the warning has been placed in a common location.
Reviewed-by: brutisso, ysr

Summary: The is_zeroed parameter is no longer used and so can be removed.
Reviewed-by: johnc, jmasa, brutisso
Contributed-by: NBrandon Mitchell <brandon@twitter.com>

Reviewed-by: johnc, ysr

Summary: Move the first part of the GC logging, including timestamp, to the start of the GC
Reviewed-by: johnc, jwilhelm

Reviewed-by: brutisso, johnc, ysr
Contributed-by: NHal Mo <kungu.mjh@taobao.com>

Summary: Simple renaming to be consistent with instanceKlass->InstanceKlass renaming
Reviewed-by: stefank, jmasa

Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: Njmasa &lt;jon.masamitsu@oracle.com&gt;, stefank &lt;stefan.karlsson@oracle.com&gt;, mgerdin &lt;mikael.gerdin@oracle.com&gt;, never <tom.rodriguez@oracle.com>

Summary: Add the flags G1EvacuationFailureALot flag (and supporting flags) to force trigger evacuation failures. The support flags control how often to trigger an evacuation failure and during which types of evacuation pause. This functionality is analogous to that of PromotionFailureALot for the other collectors.
Reviewed-by: brutisso

7178363: G1: Remove the serial code for PrintGCDetails and make it a special case of the parallel code
Summary: Also reviewed by vitalyd@gmail.com. Introduced the WorkerDataArray class. Fixed some minor logging bugs.
Reviewed-by: johnc, mgerdin

Summary: Also reviewed by: vitalyd@gmail.com. Make G1DefaultMinNewGenPercent, G1DefaultMaxNewGenPercent, G1OldCSetRegionLiveThresholdPercent and G1OldCSetRegionThresholdPercent experimental flags
Reviewed-by: ysr, johnc, jmasa

Summary: Correct the result value of G1CollectedHeap::pending_card_num(). Change the code that calculates the GC efficiency of a non-young heap region to use historical data from mixed GCs and the actual number of live bytes when predicting how long it would take to collect the region. Changes were also reviewed by Thomas Schatzl.
Reviewed-by: azeemj, brutisso

Summary: G1 does not appear to be immune to the issue described in CR 6948537 and increasing the size of old-generation PLABs appears to increase the liklihood of seeing the issue. Extend the fix for 6948537 to G1's BlockOffsetTable.
Reviewed-by: brutisso, jmasa

Summary: Employ PLABStats instances to record information about survivor and old PLABs, and use the recorded stats to adjust the sizes of survivor and old PLABS.
Reviewed-by: johnc, ysr
Contributed-by: NBrandon Mitchell <brandon@twitter.com>

Summary: Various cleanups as a prelude to introducing iterators for HeapRegions.
Reviewed-by: johnc, brutisso

Summary: Chain the fine grain PerRegionTables in an individual RSet together and free them in bulk using a single operation.
Reviewed-by: johnc, brutisso
Contributed-by: NThomas Schatzl <thomas.schatzl@jku.at>

Summary: Assertion incorrectly checks that _head is NULL and should be checking that _tail is NULL instead.
Reviewed-by: johnc
Contributed-by: NBrandon Mitchell <brandon@twitter.com>

Summary: Duplicated code from G1RemSet::par_write_ref() inlined into G1UpdateRSOrPushRefOopClosure::do_oop_nv() was showing up in profiles with a fairly high amount of CPU time. Manually inline the main part of G1RemSet::par_write_ref() to eliminate the code duplication.
Reviewed-by: azeemj, brutisso

Summary: Also reviewed by: vitalyd@gmail.com. Move the timing out of G1CollectorPolicy into the G1GCPhaseTimes class
Reviewed-by: johnc

7151532: DCmd for hotspot native memory tracking
Summary: Implementation of native memory tracking phase 1, which tracks VM native memory usage, and related DCmd
Reviewed-by: acorn, coleenp, fparain

Summary: Remove the per-thread expansion tables (PosParPRT) and associated expansion and compaction from the fine grain RSet entries. This code has been unused for a while.
Reviewed-by: johnc, brutisso
Contributed-by: NThomas Schatzl <thomas.schatzl@jku.at>

Summary: The scope of TraceMemoryManagerStats in G1CollectedHeap need to cover the call to G1MonitoringSupport::update_sizes()
Reviewed-by: johnc, jmasa

Reviewed-by: azeemj, jmasa

Summary: Simplify code, remove unused code, remove ExitAfterGCNum
Reviewed-by: huntch, johnc

Summary: Removed LOG_G and LOG_K. Moved LOG_M to where it is being used.
Reviewed-by: twisti, johnc

Summary: Before the last thread to leave a JNI critical region was able to schedule a GCLocker Initiated GC, another thread was attempting an allocation and saw that the GCLocker region was no longer active and successfully scheduled a GC. Stall allocating threads until the GCLocker Initiated GC is performed and then retry the allocation.
Reviewed-by: brutisso, huntch

Summary: Removed the assert in CompactibleFreeListSpace::check_free_list_consistency() since it was too strict. Simplified CompactibleFreeListSpace::set_cms_values() to reducde the need for asserts.
Reviewed-by: jcoomes, stefank

Reviewed-by: mgerdin, johnc

Summary: GC cause was not being set by the VM_G1CollectForAllocation VM operation.
Reviewed-by: jmasa, ysr, brutisso

Summary: Add ceiling to AdaptiveWeightedAverage
Reviewed-by: ysr, iveresov

Summary: Rename "to-space-overflow" to "to-space-exhausted", Introduce one decimal point in the size format, Add Sum to the aggregate and re-order the entries, Add number of GC workers to the log output
Reviewed-by: johnc, jwilhelm

Reviewed-by: johnc, jwilhelm, jmasa

Summary: Removed the HeapRegion::_top_at_conc_mark_count field. It is no longer needed as a result of the changes for 6888336 and 7127706. Refactored the closures that finalize and verify the liveness counting data so that common functionality was placed into a base class.
Reviewed-by: brutisso, tonyp

Summary: Fix naming style to be consistent with the predominant hotspot style.
Reviewed-by: ysr, brutisso

Summary: Cleanup of the CSet chooser class: standardize on uints for region num and indexes (instead of int, jint, etc.), make the method / field naming style more consistent, remove a lot of dead code.
Reviewed-by: johnc, brutisso

Summary: Change the type of fields / variables / etc. that represent region counts and indeces from size_t to uint.
Reviewed-by: iveresov, brutisso, jmasa, jwilhelm

Summary: use load_decode_heap_oop instead of load_decode_heap_oop_not_null
Reviewed-by: tonyp, brutisso

Summary: removed oop_verify_old_oop and allow_dirty. Also reviewed by: alexlamsl@gmail.com
Reviewed-by: jmasa, jwilhelm

Summary: Added log levels "fine", "finer" and "finest". Let PrintGC map to "fine" and PrintGCDetails map to "finer". Separated out the per worker information in the G1 logging to the "finest" level.
Reviewed-by: stefank, jwilhelm, tonyp, johnc