Read _top before _gc_time_stamp in saved_mark_word() with LoadLoad order to ensure we get a consistent view
Reviewed-by: brutisso, dcubed, dholmes, stefank
Splitting out a g1 allocator class to simply specialized allocators which can associate each allocation with a given context.
Reviewed-by: mgerdin, brutisso
Replace G1CodeRootSet with a Hashtable based implementation, merge Code Root Migration phase into Code Root Scanning
Reviewed-by: jmasa, brutisso, tschatzl
Let HeapRegionSeq manage the heap region and auxiliary data to decrease the amount of responsibilities of G1CollectedHeap, and encapsulate this work from other code.
Reviewed-by: jwilhelm, jmasa, mgerdin, brutisso
Refactor preparation for compaction during Full GC so that it lazily initializes the first compaction point. This also avoids problems later when the first region may not be committed. Also reviewed by K. Barrett.
Reviewed-by: brutisso
The free list is being maintained in a sorted fashion and old and humongous regions are allocated from the bottom of the heap while young regions are allocated at the top.
Co-authored-by: Staffan Friberg <staffan.friberg@oracle.com>
Reviewed-by: tschatzl, mgerdin
Change the code cache remembered sets data structure from a GrowableArray to a chunked list of nmethods. This makes the data structure more amenable to parallelization, and decreases freeing time.
Reviewed-by: mgerdin, brutisso
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
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
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
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
Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Co-authored-by: Stefan Karlsson <stefan.karlsson@oracle.com>
Co-authored-by: Mikael Gerdin <mikael.gerdin@oracle.com>
Co-authored-by: Tom Rodriguez <tom.rodriguez@oracle.com>
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
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
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
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
Change the type of fields / variables / etc. that represent region counts and indeces from size_t to uint.
Reviewed-by: iveresov, brutisso, jmasa, jwilhelm
Revamp of the mechanism that chooses old regions for inclusion in the CSet. It simplifies the code and introduces min and max bounds on the number of old regions added to the CSet at each mixed GC to avoid pathological cases. It also ensures that when we do a mixed GC we'll always find old regions to add to the CSet (i.e., it eliminates the case where a mixed GC will collect no old regions which can happen today).
Reviewed-by: johnc, brutisso