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Jonathan Ellis commented on CASSANDRA-5549: ------------------------------------------- bq. issue() is the normal parlance when talking about memory fences The problem is that it's not "just" a memory fence, but is tied to the Group behavior. (Once issued, the old group is sealed and a new Group started.) bq. isAfter()? WFM. > Remove Table.switchLock > ----------------------- > > Key: CASSANDRA-5549 > URL: https://issues.apache.org/jira/browse/CASSANDRA-5549 > Project: Cassandra > Issue Type: Bug > Reporter: Jonathan Ellis > Assignee: Benedict > Labels: performance > Fix For: 2.1 > > Attachments: 5549-removed-switchlock.png, 5549-sunnyvale.png > > > As discussed in CASSANDRA-5422, Table.switchLock is a bottleneck on the write > path. ReentrantReadWriteLock is not lightweight, even if there is no > contention per se between readers and writers of the lock (in Cassandra, > memtable updates and switches). -- This message was sent by Atlassian JIRA (v6.1.5#6160)