Making sure that if NewSize is set on the command line it should be used for both min and initial size even if it is re-aligned.
Reviewed-by: jwilhelm, jmasa
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
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
Setting some public integer options to specific values causes crashes or undefined GC behavior. This patchset adds the necessary argument checking for these options.
Reviewed-by: jmasa, brutisso
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
Make processing of minimum, initial and maximum heap size more intiutive by removing previous limitations on allowed values, and make error reporting consistent. Further, fix errors in ergonomic heap sizing.
Reviewed-by: johnc, jwilhelm, tamao
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
Co-authored-by: Greg Lewis <glewis@eyesbeyond.com>
Co-authored-by: Jung-uk Kim <jkim@freebsd.org>
Co-authored-by: Christos Zoulas <christos@zoulas.com>
Co-authored-by: Landon Fuller <landonf@plausible.coop>
Co-authored-by: The FreeBSD Foundation <board@freebsdfoundation.org>
Co-authored-by: Michael Franz <mvfranz@gmail.com>
Co-authored-by: Roger Hoover <rhoover@apple.com>
Co-authored-by: Alexander Strange <astrange@apple.com>
Reviewed-by: kvn, twisti, jrose
BlockOffsetArrayUseUnallocatedBlock was intended to be turned off as part of BUG 6948538 but a code line in collectorPolicy.cpp actually kept it turned on.
Reviewed-by: jwilhelm, ysr
6627787: CMS: JVM refuses to start up with -Xms16m -Xmx16m
7000125: CMS: Anti-monotone young gen sizing with respect to maximum whole heap size specification
7027529: CMS: retire CMSUseOldDefaults flag
Simplify CMS heap sizing code, relying on ergonomic initial sizing consistent with other collectors for the most part, controlling only young gen sizing to rein in pause times. Make CMS young gen sizing default statically cpu-dependant. Remove inconsistencies wrt generation sizing and policy code, allowing for the fixing for 6627787 and 7000125. For 7027529, retire the flag CMSUseOldDefaults which had been introduced as a bridge from JDK 5 to JDK 6 a number of years ago.
Reviewed-by: brutisso, poonam
7002546: regression on SpecJbb2005 on 7b118 comparing to 7b117 on small heaps
Relaxed assertion checking related to incremental_collection_failed flag to allow for ExplicitGCInvokesConcurrent behaviour where we do not want a failing scavenge to bail to a stop-world collection. Parameterized incremental_collection_will_fail() so we can selectively use, or not use, as appropriate, the statistical prediction at specific use sites. This essentially reverts the scavenge bail-out logic to what it was prior to some recent changes that had inadvertently started using the statistical prediction which can be noisy in the presence of bursty loads. Added some associated verbose non-product debugging messages.
Reviewed-by: johnc, tonyp
Deprecated HandlePromotionFailure, removing the ability to turn off that feature, did away with one epoch look-ahead when deciding if a scavenge is likely to fail, relying on current data.
Reviewed-by: jmasa, johnc, poonam