Thanks for looking into this. If you have a way to reproduce this the best thing to do is create a ticket at https://issues.apache.org/jira/browse/CASSANDRA as 2.0 is still under development.
Cheers ----------------- Aaron Morton Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 26/07/2013, at 11:29 AM, Soumava Ghosh <soum...@cs.utexas.edu> wrote: > Hi, > > I have test setup where clients randomly make a controlled number of cas() > requests (among other requests) at a cluster of cassandra 2.0 servers. After > one point, I'm seeing that all requests are pending and my client's > throughput has reduced to 0.0 for all kinds of requests. For this specific > case I had 10 clients each making around 30 cas() requests per second at a > cluster of 72 instances of cassandra. > > Clients are set up to register a request as a success after the cas() call > returns with CASResult.success = true, else an exception is thrown. Since I > see that no client requests were actually registered and no exceptions were > thrown, which indicates that the cas() call itself is hung. > > On the server side, I see Paxos logs as follows - they go on for 50 log files > for each of the servers involved, and they span at least an hour. I have > marked a particular instance where the prepare response is true but the > propose response is false from all the involved servers: > > At the Paxos Initiator: None of the files among the 50 system logs have the > phrase 'Propose response true', these logs just go on and on. > > DEBUG [RequestResponseStage:110] 2013-07-25 15:09:05,332 PrepareCallback.java > (line 58) Prepare response PrepareResponse(true, > Commit(d145fe46f5d02a54b5ea95852f94c402, > 1a0c4220-f561-11e2-a409-019f62d610d7, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])), > Commit(d145fe46f5d02a54b5ea95852f94c402, > d2093120-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,]))) from > /17.163.7.195 > > DEBUG [RequestResponseStage:92] 2013-07-25 15:09:05,346 PrepareCallback.java > (line 58) Prepare response PrepareResponse(true, > Commit(d145fe46f5d02a54b5ea95852f94c402, > 1a0c4220-f561-11e2-a409-019f62d610d7, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])), > Commit(d145fe46f5d02a54b5ea95852f94c402, > d2093120-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,]))) from > /17.163.7.184 > > DEBUG [RequestResponseStage:98] 2013-07-25 15:09:05,347 PrepareCallback.java > (line 58) Prepare response PrepareResponse(true, > Commit(d145fe46f5d02a54b5ea95852f94c402, > 1a0c4220-f561-11e2-a409-019f62d610d7, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])), > Commit(d145fe46f5d02a54b5ea95852f94c402, > d2093120-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,]))) from > /17.163.7.20 > > DEBUG [RequestResponseStage:93] 2013-07-25 15:09:05,350 ProposeCallback.java > (line 44) Propose response false from /17.163.7.20 > DEBUG [RequestResponseStage:100] 2013-07-25 15:09:05,350 ProposeCallback.java > (line 44) Propose response false from /17.163.7.184 > DEBUG [RequestResponseStage:111] 2013-07-25 15:09:05,350 ProposeCallback.java > (line 44) Propose response false from /17.163.7.195 > > DEBUG [RequestResponseStage:102] 2013-07-25 15:09:05,351 PrepareCallback.java > (line 58) Prepare response PrepareResponse(true, > Commit(d145fe46f5d02a54b5ea95852f94c402, > 1a0c4220-f561-11e2-a409-019f62d610d7, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])), > Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c3e60-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,]))) from > /17.163.7.195 > > DEBUG [RequestResponseStage:107] 2013-07-25 15:09:05,352 PrepareCallback.java > (line 58) Prepare response PrepareResponse(true, > Commit(d145fe46f5d02a54b5ea95852f94c402, > 1a0c4220-f561-11e2-a409-019f62d610d7, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])), > Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c3e60-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,]))) from > /17.163.7.20 > > DEBUG [RequestResponseStage:108] 2013-07-25 15:09:05,352 PrepareCallback.java > (line 58) Prepare response PrepareResponse(true, > Commit(d145fe46f5d02a54b5ea95852f94c402, > 1a0c4220-f561-11e2-a409-019f62d610d7, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])), > Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c3e60-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,]))) from > /17.163.7.184 > > DEBUG [RequestResponseStage:104] 2013-07-25 15:09:05,352 ProposeCallback.java > (line 44) Propose response false from /17.163.7.20 > DEBUG [RequestResponseStage:99] 2013-07-25 15:09:05,353 ProposeCallback.java > (line 44) Propose response false from /17.163.7.195 > DEBUG [RequestResponseStage:105] 2013-07-25 15:09:05,353 ProposeCallback.java > (line 44) Propose response false from /17.163.7.184 > > At 17.163.7.20: > > DEBUG [MutationStage:58] 2013-07-25 15:09:05,347 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20b05e0-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20b7b10-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > DEBUG [MutationStage:40] 2013-07-25 15:09:05,349 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20b7b10-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20bc930-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > DEBUG [MutationStage:42] 2013-07-25 15:09:05,351 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20bc930-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c6570-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > DEBUG [MutationStage:43] 2013-07-25 15:09:05,352 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c3e60-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c6570-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > At 17.163.7.195: > > DEBUG [MutationStage:33] 2013-07-25 15:09:05,352 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20bc930-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c6570-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > DEBUG [RequestResponseStage:38] 2013-07-25 15:09:05,352 PrepareCallback.java > (line 58) Prepare response PrepareResponse(true, > Commit(658db3eababc5629b8bcb77dc84db81a, > 0193c330-f561-11e2-ad78-7bbb6a42087c, ColumnFamily(P > [62caa268bd7e90050000000000000001:false:21@1374780776163000,])), > Commit(658db3eababc5629b8bcb77dc84db81a, > d20c3e60-f576-11e2-b3a3-edb9f71dce8f, ColumnFamily(P > [62caa268bd7e90050000000000000001:false:21@1374780776163000,]))) from > /17.163.7.162 > > DEBUG [RequestResponseStage:48] 2013-07-25 15:09:05,353 ProposeCallback.java > (line 44) Propose response false from /17.163.7.194 > DEBUG [RequestResponseStage:54] 2013-07-25 15:09:05,353 ProposeCallback.java > (line 44) Propose response false from /17.163.7.162 > > DEBUG [MutationStage:35] 2013-07-25 15:09:05,353 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c3e60-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c6570-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > At 17.163.7.184: > > DEBUG [MutationStage:53] 2013-07-25 15:09:05,347 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20b05e0-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20b7b10-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > DEBUG [MutationStage:38] 2013-07-25 15:09:05,348 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20b7b10-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20bc930-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > DEBUG [MutationStage:64] 2013-07-25 15:09:05,351 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20bc930-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c6570-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > DEBUG [MutationStage:33] 2013-07-25 15:09:05,351 PaxosState.java (line 100) > accept requested for Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c3e60-f576-11e2-9bbe-bf2ad4fe6707, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) but > inProgress is now Commit(d145fe46f5d02a54b5ea95852f94c402, > d20c6570-f576-11e2-a57e-a154d605509d, ColumnFamily(P > [81d271b2125c59cb0000000000000003:false:27@1374780817218000,])) > > > Thanks, > Soumava