a) s/#3/#6/ in previous comment.



b) Tested 5.5 --------> 5.6, works even with multiple sysbench threads.


c) 5.6 --------> 5.5 OTOH fails even with sysbench of 1 thread. (so multi-threading is not an issue here):

^[[A131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 2th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 3th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 4th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 5th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 6th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 7th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 8th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 9th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970
131114 21:57:46 [Warning] WSREP: Failed to apply app buffer: seqno: 9970, status: 1
         at galera/src/replicator_smm.cpp:apply_wscoll():57
Retrying 10th time
131114 21:57:46 [ERROR] Slave SQL: Could not execute Update_rows event on table sbtest.sbtest1; Column 'k' cannot be null, Error_code: 1048; Duplicate entry '15073' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log FIRST, end_log_pos 174, Error_code: 1062
131114 21:57:46 [Warning] WSREP: RBR event 3 Update_rows apply warning: 121, 9970

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