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
Count enable_icms() and disable_icms() events so as to prevent inteference between concurrent calls, which can cause the iCMS thread to be left stranded in icms_wait() with an unserviced request and no young allocations to unwedge it.
Reviewed-by: jcoomes, poonam
Closed a timing hole during which concurrent full gc requests can be missed. The hole can increase the latency of the response to a full gc request by up to the value of CMSWaitDuration. If CMSWaitDuration=0 is, as currently, interpreted as an unbounded wait, suitable in certain tuning scenarios, the application can potentially hang. Made two obscure tunables, including CMSWaitDuration, manageable.
Reviewed-by: jcoomes, tonyp
Inserted missing yield(check)s in closures used during the work-stealing phase of parallel concurrent marking, a missing synchronous yield-request in the cms perm gen allocation path, and a terminator-terminator for the offer_termination invocation that monitors the yield status of the concurrent marking task. Elaborated some documentation comments and made some task queue termination loop flags configurable at start-up to aid debugging in the field.
Reviewed-by: jmasa, johnc, poonam
