Actually I may be wrong... But I would still try with 3-nodes.
On Wed, Dec 4, 2013 at 11:04 PM, J. Ryan Earl <o...@jryanearl.us> wrote: > You're using only 2 nodes, Paxos requires a minimum of 3 nodes to > establish a quorum. Cassandra should likely disallow lightweight > transactions entirely in a 2-node scenario. > > > On Tue, Dec 3, 2013 at 8:33 PM, Jim Xu <jimxu...@gmail.com> wrote: > >> Hi all, >> >> I use two threads to test lightweight transaction. Each thread execute >> "insert into test_table(column1,column2) values (i, thread_id) if not >> exists" N times, and "i" is in the range of 0~N. If N is a small number, >> it is ok,some row are inserted by thread 1 and other rows are inserted >> by thread 2; if N is a big number, I will get >> TimedoutException(acknowledged_by:1, paxos_in_progress:true) and have >> the following two different results: >> >> 1) only one thread throws the exception, and this thread successfully >> inserts the value; >> 2) both the two threads throw the exception, and no value is inserted >> into the table. >> >> I except that some rows in test_table are inserted by thread 1 and others >> inserted by thread 2. If one thread inserts a row which has be in the >> table, >> the row will not be modified and the thread will continue to insert the >> next row. >> >> I think that is lightweight transaction's function, but why I get the >> exception and how to avoid it. >> I try to enlarge cas_contention_timeout_in_ms in cassandra.yaml, but it >> does not work. >> >> my cassandra version is 2.0.3, and the cluster has two nodes with >> keypsace's replication_factor is 2. >> >> Best Regards >> Jim Xu >> > >
