Percona XtraDB Cluster moved to https://jira.percona.com/projects/PXC

WSREP: conc slot cancel not supported

Bug #1234229 reported by Raghavendra D Prabhu on 2013-10-02

This bug affects 1 person

	Status	Importance	Assigned to	Milestone
MySQL patches by Codership	Fix Released	Undecided	Seppo Jaakola	MySQL patches by Codership 5.6.14-25.1
Percona XtraDB Cluster moved to https://jira.percona.com/projects/PXC	Status tracked in 5.6
5.5	Invalid	Undecided	Unassigned
5.6	Fix Released	Undecided	Unassigned	Percona XtraDB Cluster moved to https://jira.percona.com/projects/PXC 5.6.14-25.1

Bug Description

Getting this in error log a lot.

=======================================================

wsrep_srv_conc_cancel_wait(
/*==================*/
trx_t* trx) /*!< in: transaction object associated with the
   thread */
{
#ifdef HAVE_ATOMIC_BUILTINS
fprintf(stderr, "WSREP: conc slot cancel not supported\n");
#else
os_fast_mutex_lock(&srv_conc_mutex);
if (trx->wsrep_event) {
  if (wsrep_debug)
   fprintf(stderr, "WSREP: conc slot cancel\n");
  os_event_set(trx->wsrep_event);
}
os_fast_mutex_unlock(&srv_conc_mutex);
#endif
}

===============================================

this is in abort trx path.

Binaries on most of the modern platforms have atomic builtins enabled.

Related branches

lp://staging/percona-xtradb-cluster

Seppo Jaakola (seppo-jaakola) on 2013-10-02

Changed in codership-mysql:
assignee:	nobody → Seppo Jaakola (seppo-jaakola)

Revision history for this message

Raghavendra D Prabhu (raghavendra-prabhu) wrote on 2013-10-02:

a) If this is redundant, then a

if (wsrep_debug) { } is required since it is otherwise in the error log a lot.

b) srv_conc_enter_innodb_without_atomics seems to be only place where trx->wsrep_event is used, srv_conc_enter_innodb_without_atomics is called only when ATOMIC_BUILTINS are not defined. Hence, it makes sense to wrap wsrep_srv_conc_cancel_wait and its calls inside #ifdef HAVE_ATOMIC_BUILTINS as well.

Raghavendra D Prabhu (raghavendra-prabhu) on 2013-10-02

Changed in percona-xtradb-cluster:
milestone:	none → 5.6.13-24.0
milestone:	5.6.13-24.0 → none

Seppo Jaakola (seppo-jaakola) on 2013-10-11

Changed in codership-mysql:
status:	New → In Progress

Revision history for this message

Seppo Jaakola (seppo-jaakola) wrote on 2013-10-11:

Moved high priority thread innodb concurrency check in higher level, high priority threads can enter with no limits.
Cancelling of threads waiting for innodb enter must be support both for with and without ATOMICS implementation.
Now WITH_ATOMICS case is sorted out so that BF aborting threads can enter innodb by force, after their os sleep ends.

Fix pushed in revision: http://bazaar.launchpad.net/~codership/codership-mysql/5.6/revision/3966