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: 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>

Summary: Fixed the output of G1SummarizeRSetStats: too small datatype for the number of concurrently processed cards, added concurrent remembered set thread time retrieval for Linux and Windows (BSD uses os::elapsedTime() now), and other cleanup. The information presented during VM operation is now relative to the previous output, not always cumulative if G1SummarizeRSetStatsPeriod > 0. At VM exit, the code prints a cumulative summary.
Reviewed-by: johnc, jwilhelm

8014405: G1: PerRegionTable::fl_mem_size() calculates size of the free list using wrong element sizes
Summary: Instead of using a simple sizeof(), ask the PerRegionTable class about its size when iterating over the free list.
Reviewed-by: jwilhelm, brutisso

Reviewed-by: brutisso, tschatzl

8010738: G1: Output for full GCs with +PrintGCDetails should contain perm gen size/meta data change info
Summary: Include metaspace information (used, allocated, reserved) in the PrintGCDetails output for full GCs.
Reviewed-by: poonam, jmasa, brutisso

Summary: Improve the output of G1PrintRegionLivenessInfo by adding a per-region remembered set size information column
Reviewed-by: jwilhelm, johnc

Summary: Mismatch in the card number calculation between next and previous committed sizes of the card counts table.
Reviewed-by: jmasa, tschatzl

Summary: The fix of 8010992, disable use of global operator new and new[] which caused failure on some tests. This takes two of the bugs also add ALLOW_OPERATOR_NEW_USAGE to prevent crash for third party code calling operator new of jvm on certain platforms.
Reviewed-by: coleenp, dholmes, zgu
Contributed-by: yumin.qi@oracle.com

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: tschatzl, jmasa

Summary: Refactored shrink_by() to only use region counts and not byte sizes
Reviewed-by: johnc, tschatzl

Summary: Make sure max alignemnt is at least as large as min alignment
Reviewed-by: johnc, jmasa, tschatzl

Reviewed-by: coleenp, zgu, hseigel

Reviewed-by: coleenp, mgerdin

Reviewed-by: johnc, brutisso

Summary: anti-delta fix for 8010992 until 8012902 can be fixed
Reviewed-by: acorn, minqi, rdurbin

Summary: disable use of global operator new and new[] which could cause unexpected exception and escape from NMT tracking.
Reviewed-by: coleenp, dholmes, zgu
Contributed-by: yumin.qi@oracle.com

Reviewed-by: brutisso, jmasa

Summary: Add the -Wunused-function flag and remove a number of unused functions.
Reviewed-by: dholmes, coleenp, kvn

Summary: Move the calculation and recording of eden capacity to the start of a GC and print a detailed heap transition for full GCs.
Reviewed-by: tschatzl, jmasa

Summary: Some parts of the G1 heap can only be walked during a safepoint. Skip verifying these parts of the heap when verifying during JVM startup.
Reviewed-by: brutisso, tschatzl

Summary: Keep a counter of how many times we were stalled by the GC locker, add a diagnostic flag which sets the limit.
Reviewed-by: brutisso, ehelin, johnc

Summary: If the marking stack overflows while the marking tasks are draining the SATB buffers, remark will exit with some SATB buffers left unprocessed. Relax the guarantee to allow for overflow.
Reviewed-by: jmasa, brutisso

Summary: Skip reference processing if the global marking stack overflows during remark. Refactor and rename set_phase(); move code that sets the concurrency level into its own routine. Do not call set_phase() from within parallel reference processing; use the concurrency level routine instead. The marking state should only set reset by CMTask[0] during the concurrent phase of the marking cycle; if an overflow occurs at any stage during the remark, the marking state will be reset after reference processing.
Reviewed-by: brutisso, jmasa

Summary: In CMTask::do_marking_step(), Skip offering termination and entering the first and second synchronization barriers if called from a serial context, i.e. the VM thread.
Reviewed-by: brutisso, tschatzl

Summary: ASSERT and other symbols used incorrectly with #if are supposed to be defined or not.
Reviewed-by: dholmes, mikael

Summary: Update the task local finger to the start of the next object when marking aborts, in order to avoid the redundant scanning of all 0's when the marking task restarts, if otherwise updating to the next word. In addition, reuse the routine nextObject() in routine iterate().
Reviewed-by: johnc, ysr
Contributed-by: Ntamao <tao.mao@oracle.com>

Summary: Stop adding old regions to collection set when the remaining reclaimable bytes reaches, or goes below, G1HeapWastePercent. Changes were also reviewed by Vitaly Davidovich <vitalyd@gmail.com>.
Reviewed-by: brutisso

Reviewed-by: mgerdin, coleenp

Summary: Stack allocate instances of HeapRegionRemSetIterator during RSet scanning.
Reviewed-by: brutisso, jwilhelm

Reviewed-by: tschatzl, jmasa