8027455: Improve symbol table scan times during gc pauses
Summary: Parallelize string table and symbol table scan during remark and full GC. Some additional statistics output if the experimental flag G1TraceStringSymbolTableScrubbing is set.
Reviewed-by: mgerdin, coleenp, brutisso

Summary: Copyright year updated for files modified during 2013
Reviewed-by: twisti, iveresov

Reviewed-by: brutisso, jmasa, jwilhelm

Reviewed-by: dholmes, egahlin

Summary: Change checks for isHumongous() to continuesHumongous() as installing a code root for a humongous object is valid, but not for continuations of humongous objects. Cleaned up asserts.
Reviewed-by: jmasa, tamao

7057939: jmap shows MaxNewSize=4GB when Java is using parallel collector
Summary: Major cleanup of the collectorpolicy classes
Reviewed-by: tschatzl, jcoomes

Summary: The field G1AllocRegion::_alloc_region needs to be declared volatile as it is used with that intention. Otherwise the compiler may generate the code that reloads the value which might have changed in the meantime, leading to spurious crashes.
Reviewed-by: iveresov, simonis, tschatzl
Contributed-by: NAxel Siebenborn <axel.siebenborn@sap.com>

Summary: Changed the use of %d to SIZE_FORMAT macro in format string when printing size_t values.
Reviewed-by: stefank, ehelin

Summary: Cleanup related to the NewSize and MaxNewSize bugs
Reviewed-by: tschatzl, jcoomes, ehelin

Summary: Removed the GenRemSet::rem_set_name() since we only have one remset.
Reviewed-by: stefank, mgerdin, tschatzl

Summary: Exit with an error if incompatible NewSize and MaxNeSize are set
Reviewed-by: brutisso, tschatzl

Summary: Add a StoreLoad barrier in the G1 post-barrier to fix a race with concurrent refinement. Also-reviewed-by: martin.doerr@sap.com
Reviewed-by: iveresov, tschatzl, brutisso, roland, kvn

Summary: Use instance variables directly within the collector policy classes and remove unused setters.
Reviewed-by: tschatzl, jcoomes

Reviewed-by: tschatzl, jwilhelm, jmasa

8025441: G1: assert "assert(thread < _num_vtimes) failed: just checking" fails when G1ConcRefinementThreads > ParallelGCThreads
Summary: The initialization for the remembered set summary data structures used the wrong thread count, i.e. number of worker threads instead of number of refinement threads.
Reviewed-by: brutisso

Summary: Enable CHECK_UNHANDLED_OOPS in fastdebug builds across all supported platforms.
Reviewed-by: coleenp, hseigel, dholmes, stefank, twisti, ihse, rdurbin
Contributed-by: lois.foltan@oracle.com

Summary: Add G1BiasedArray<T> that is an array where each element represents a fixed-sized subdivision of the heap. Use this abstraction to refactor the HeapRegionSeq class.
Reviewed-by: brutisso

Summary: Move some G1 specific code from CardTableModRefBS to G1SATBCardTableModRefBS.
Reviewed-by: brutisso, tschatzl, ehelin

Summary: Add memory consumption breakdown on a per region type in the G1 remembered set summary statistics. This simplifies remembered set memory consumption analysis.
Reviewed-by: brutisso

Reviewed-by: kvn, coleenp

Reviewed-by: brutisso, tschatzl

Summary: Use conservative assumptions of required alignment for the various garbage collector components into account when determining the maximum heap size that supports compressed oops. Using this conservative value avoids several circular dependencies in the calculation.
Reviewed-by: stefank, dholmes

Summary: Correctly calculate the initialization value for the shift between object start and bitmap bit in the G1 mark bitmaps.
Reviewed-by: tonyp

8019902: G1: Use the average heap size rather than the minimum heap size to calculate the region size
Reviewed-by: tonyp, tschatzl, sjohanss

Reviewed-by: mgerdin, stefank

Reviewed-by: tonyp, tschatzl

Summary: Replace the broken large pages implementation on Linux. New flag: -XX:+UseTransparentHugePages - Linux specific flag to turn on transparent huge page hinting with madvise(..., MAP_HUGETLB). Changed behavior: -XX:+UseLargePages - tries to use -XX:+UseTransparentHugePages before trying other large pages implementations (on Linux). Changed behavior: -XX:+UseHugeTLBFS - Use upfront allocation of Large Pages instead of using the broken implementation to dynamically committing large pages. Changed behavior: -XX:LargePageSizeInBytes - Turned off the ability to use this flag on Linux and provides warning to user if set to a value different than the OS chosen large page size. Changed behavior: Setting no large page size - Now defaults to use -XX:UseTransparentHugePages if the OS supports it. Previously, -XX:+UseHugeTLBFS was chosen if the OS was configured to use large pages.
Reviewed-by: tschatzl, dcubed, brutisso

Reviewed-by: stefank, mgerdin

Summary: Add a list of nmethods to the RSet for a region that contain references into the region. Skip scanning the code cache during root scanning and scan the nmethod lists during RSet scanning instead.
Reviewed-by: tschatzl, brutisso, mgerdin, twisti, kvn

Reviewed-by: mgerdin, coleenp, hseigel, jmasa, ctornqvi

Reviewed-by: tschatzl, jmasa

Reviewed-by: tschatzl, jmasa

Summary: Take _last_young_gc into account when deciding on starting a concurrent mark. Also reviewed-by: per.liden@oracle.com.
Reviewed-by: tschatzl, johnc

Summary: Remove -Xaprof and Klass::_alloc_count & ArrayKlass::_alloc_size.
Reviewed-by: stefank, coleenp

Summary: The assert is invalid when a card is being refined by two different threads and its count crosses the hot threshold - the refinement count will be updated once by each thread triggering the assert. Remove the assert and update the count using a bounded expression.
Reviewed-by: jmasa, tamao, brutisso

Reviewed-by: tschatzl, brutisso, jmasa, ysr
Contributed-by: per.liden@oracle.com

Summary: Minimize redundant verifications of Klasses.
Reviewed-by: hseigel, jmasa

Reviewed-by: acorn, coleenp, sla
Contributed-by: NKaren Kinnear &lt;karen.kinnear@oracle.com&gt;, Bengt Rutisson &lt;bengt.rutisson@oracle.com&gt;, Calvin Cheung &lt;calvin.cheung@oracle.com&gt;, Erik Gahlin &lt;erik.gahlin@oracle.com&gt;, Erik Helin &lt;erik.helin@oracle.com&gt;, Jesper Wilhelmsson &lt;jesper.wilhelmsson@oracle.com&gt;, Keith McGuigan &lt;keith.mcguigan@oracle.com&gt;, Mattias Tobiasson &lt;mattias.tobiasson@oracle.com&gt;, Markus Gronlund &lt;markus.gronlund@oracle.com&gt;, Mikael Auno &lt;mikael.auno@oracle.com&gt;, Nils Eliasson &lt;nils.eliasson@oracle.com&gt;, Nils Loodin &lt;nils.loodin@oracle.com&gt;, Rickard Backman &lt;rickard.backman@oracle.com&gt;, Staffan Larsen &lt;staffan.larsen@oracle.com&gt;, Stefan Karlsson &lt;stefan.karlsson@oracle.com&gt;, Yekaterina Kantserova <yekaterina.kantserova@oracle.com>

Summary: In a full GC, move the verification after the GC to after RSet rebuilding. Verify RSet entries during a full GC under control of a flag.
Reviewed-by: tschatzl, brutisso

Summary: Create G1ParGCAllocBufferContainer to contain two buffers instead of previously using one buffer, in order to hold the first priority buffer longer. Thus, when some large objects hits the value of free space left in the first priority buffer it has an alternative to fit in the second priority buffer while the first priority buffer is given more chances to try allocating smaller objects. Overall, it will improve heap space efficiency.
Reviewed-by: johnc, jmasa, brutisso
Contributed-by: Ntamao <tao.mao@oracle.com>