I have reviewed Doug's code, just need someone to quickly review the test code.
Paul. On Dec 2, 2013, at 5:29 PM, Paul Sandoz <paul.san...@oracle.com> wrote: > Hi, > > http://cr.openjdk.java.net/~psandoz/tl/JDK-8028564-concurrent-resize/webrev/ > > This patch is contributed by Doug Lea and fixes two issues found in > ConcurrentHashMap: > > 1) A problem with concurrent resizes; and > > 2) The skipping of elements when traversing through bins that are trees of > entries. > > Both of these issues can result in elements "disappearing" from the map, > either because an update operation such as put failed, or because a contains > operation failed to find the entry in the map. > > Issue 1) was causing stream tests to fail intermittently on systems with many > cores (24 to 32) (furthermore the CHM-based JDK test ToArray was also > intermittently failing with less frequency). > > After some investigation the cause was distilled down to the use of > ConcurrentHashMap in the F/J task used by Stream.forEachOrdered. > > Issue 2) was serendipitously reported on concurrentcy-interest just yesterday > :-) > > Both issues have test cases associated with them that have been tuned to > reproduce on systems with low cores i.e. my MacBook! > > Paul.
