pt-osc fails when executed from passive node while active node was receiving writes on same table being altered.
pt-online-schema-change --alter="ENGINE=INNODB" D=sb,t=sbtest1,u=root --execute --max-flow-ctl 0
No slaves found. See --recursion-method if host pxc2 has slaves.
Not checking slave lag because no slaves were found and --check-slave-lag was not specified.
# A software update is available:
# * The current version for Percona::Toolkit is 2.2.20.
Operation, tries, wait:
analyze_table, 10, 1
copy_rows, 10, 0.25
create_triggers, 10, 1
drop_triggers, 10, 1
swap_tables, 10, 1
update_foreign_keys, 10, 1
Altering `sb`.`sbtest1`...
Creating new table...
Created new table sb._sbtest1_new OK.
Altering new table...
Altered `sb`.`_sbtest1_new` OK.
2017-01-20T08:36:13 Creating triggers...
2017-01-20T08:36:13 Created triggers OK.
2017-01-20T08:36:13 Copying approximately 11133 rows...
2017-01-20T08:36:18 Dropping triggers...
2017-01-20T08:36:18 Dropped triggers OK.
2017-01-20T08:36:18 Dropping new table...
2017-01-20T08:36:18 Dropped new table OK.
`sb`.`sbtest1` was not altered.
2017-01-20T08:36:18 Error copying rows from `sb`.`sbtest1` to `sb`.`_sbtest1_new`: 2017-01-20T08:36:18 Copying rows caused a MySQL error 1317:
Level: Error
Code: 1317
Message: Query execution was interrupted
Query: INSERT LOW_PRIORITY IGNORE INTO `sb`.`_sbtest1_new` (`id`, `k`, `c`, `pad`) SELECT `id`, `k`, `c`, `pad` FROM `sb`.`sbtest1` FORCE INDEX(`PRIMARY`) WHERE ((`id` >= ?)) AND ((`id` <= ?)) LOCK IN SHARE MODE /*pt-online-schema-change 1708 copy nibble*/
From node's error log I see the following:
2017-01-20 08:45:20 1634 [Note] WSREP: MDL BF-BF conflict
schema: sb
request: (2 seqno 5656596 wsrep (1, 1, 0) cmd 0 146 (null))
granted: (9 seqno 5656595 wsrep (2, 1, 0) cmd 3 105 DROP TRIGGER IF EXISTS `sb`.`pt_osc_sb_sbtest1_del`)
How to repeat:
using 3-node PXC
run sysbench on node1 inserting to sbtest1
run pt-osc on node2 on same table sbtest1
If pt-osc is executed on node1 while table is updated, pt-osc does not fail and actually completes.
Marking as confirmed since this is repeatable also based on customer account. Will be interested in developer feedback.