unknown d6bc2d60e5 BUG#20697 slave fails to rollback replicated transaction hang over innodb_lock_wait_timeou ...

Transaction on the slave sql thread got blocked against a slave's mysqld local ta's
lock. Since the default, slave-transaction-retries=10, there was replaying of the 
replicated ta. That failed because of a new started from 5.0.13 policy not to rollback
a timed-out transaction. Effectively the first round of a timed-out ta becomes committed
by the replaying's first "BEGIN".

It was decided to backport already existed method working in 5.1 implemented in
bug #16228 for handling symmetrical deadlock problem. That patch introduced end_trans
execution whenever a replicated ta deadlocks or timed-out.

Note, that this solution can be practically suboptimal - in the light of the changed behavior
due to timeout we still could replay only the last statement -  only with a high rate of timeouting
replicated transactions.


mysql-test/r/rpl_deadlock.result:
  results changed
mysql-test/t/rpl_deadlock.test:
  Refining the timeout part of the test to display that the timed-out transaction
  is rolled back prior its replaying by slave sql.
  Non-zero select's count would mean the first round work became persistent - wrong.
sql/slave.cc:
  applying bug#16228 fix, approbated for deadlock use case in 5.1, almost verbatim. 
  Another alternative to replay only the offending statement requires significant
  efforts, incl design work.

2006-10-11 10:16:37 +03:00

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