[ https://issues.apache.org/jira/browse/CASSANDRA-5830?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Soumava Ghosh updated CASSANDRA-5830: ------------------------------------- Labels: 2.0 cas paxos (was: ) > Paxos loops endlessly due to faulty condition check > --------------------------------------------------- > > Key: CASSANDRA-5830 > URL: https://issues.apache.org/jira/browse/CASSANDRA-5830 > Project: Cassandra > Issue Type: Bug > Affects Versions: 2.0 beta 2 > Reporter: Soumava Ghosh > Labels: 2.0, cas, paxos > > Following is the code segment (StorageProxy.java:361) which causes the issue: > Start is the start time of the paxos, is always less than the current system > time, and therefore the negative difference is always less than the timeout. > {code:title=StorageProxy.java|borderStyle=solid} > private static UUID beginAndRepairPaxos(long start, ByteBuffer key, > CFMetaData metadata, List<InetAddress> liveEndpoints, int > requiredParticipants, ConsistencyLevel consistencyForPaxos) > throws WriteTimeoutException > { > long timeout = > TimeUnit.MILLISECONDS.toNanos(DatabaseDescriptor.getCasContentionTimeout()); > PrepareCallback summary = null; > while (start - System.nanoTime() < timeout) > { > long ballotMillis = summary == null > ? System.currentTimeMillis() > : Math.max(System.currentTimeMillis(), 1 + > UUIDGen.unixTimestamp(summary.inProgressCommit.ballot)); > UUID ballot = UUIDGen.getTimeUUID(ballotMillis); > {code} > Here, the paxos gets stuck when PREPARE returns 'true' but with > inProgressCommit. The code in StorageProxy.java:beginAndRepairPaxos() then > tries to issue a PROPOSE and COMMIT for the inProgressCommit, and if it > repeatedly receives 'false' as a PREPARE_RESPONSE it gets stuck in an endless > loop until PREPARE_RESPONSE is true. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira