[ https://jira.jboss.org/jira/browse/JGRP-1122?page=com.atlassian.jira.plug... ] Bela Ban commented on JGRP-1122: -------------------------------- The down code: entry.lock(); // threads will only sync if they access the same entry try { seqno=entry.sent_msgs_seqno; send_conn_id=entry.send_conn_id; hdr=new UnicastHeader(UnicastHeader.DATA, seqno, send_conn_id, seqno == DEFAULT_FIRST_SEQNO); msg.putHeader(getName(), hdr); // AckSenderWindow.add() is costly as it calls Retransmitter.add() which calls TimeScheduler.schedule(), // which adds the scheduled task to a DelayQueue, which does costly tree rebalancing. // In 2.9 (or 3.0), we'll replace use of ScheduledThreadPoolExecutor in TimeScheduler with // a ConcurrentSkipListMap, which is faster (log(n) access cost for most ops). CSLM requires JDK 1.6 // Note that moving the next statement out of the lock scope made for some really ugly code, that's // why this was reverted ! entry.sent_msgs.add(seqno, msg); // add *including* UnicastHeader, adds to retransmitter entry.sent_msgs_seqno++; } finally { entry.unlock(); } could be changed to *not* acquire any lock at all (the lock showed up as a hotsport for thread contention). However this would mean that a seqno could be lost, for example if we have a temp OOME ! SOLUTION: Keep track of 'lost' seqnos, e.g. +1 +2 -3 +4 +5, where 3 is lost. We cannot send 3 later because this would make it get delivered *before* messages which were sent after 3 ! Piggyback the NIL information for 3 in other UNICAST messages and skip 3 on the receiver. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira

[ https://jira.jboss.org/jira/browse/JGRP-1122?page=com.atlassian.jira.plug... ] Bela Ban resolved JGRP-1122. ---------------------------- Resolution: Done -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira