Tasks are not single threading - getting deadlocks for tasks

We are getting deadlocks when doing platform upgrades. Is there a setting that will prevent multiple tasks from running at once?

debian version 7.11
boa version 3.2.0

errors
WD node: PDOException: SQLSTATE[40001]: Serialization failure: 1213 Deadlock found when trying to get lock; try restarting transaction: INSERT INTO {node_access} (nid, realm, gid, grant_view, grant_update, grant_delete) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5); Array
(
[:db_insert_placeholder_0] => 11244
[:db_insert_placeholder_1] => hosting task
[:db_insert_placeholder_2] => 1
[:db_insert_placeholder_3] => 1
[:db_insert_placeholder_4] => 0
[:db_insert_placeholder_5] => 0
)
in node_access_write_grants() (line 3591 of /data/disk/o1/aegir/distro/015/modules/node/node.module).

exception 'PDOException' with message 'SQLSTATE[40001]: Serialization failure: 1213 Deadlock found when trying to get lock; try restarting transaction' in /data/disk/o1/aegir/distro/015/includes/database/database.inc:2227
Stack trace:
#0 /data/disk/o1/aegir/distro/015/includes/database/database.inc(2227): PDOStatement->execute(Array)
#1 /data/disk/o1/aegir/distro/015/includes/database/database.inc(697): DatabaseStatementBase->execute(Array, Array)
#2 /data/disk/o1/aegir/distro/015/includes/database/mysql/query.inc(36): DatabaseConnection->query('INSERT INTO {no...', Array, Array)
#3 /data/disk/o1/aegir/distro/015/modules/node/node.module(3591): InsertQuery_mysql->execute()
#4 /data/disk/o1/aegir/distro/015/modules/node/node.module(3537): node_access_write_grants(Object(stdClass), Array, NULL, true)
#5 /data/disk/o1/aegir/distro/015/modules/node/node.module(1184): node_access_acquire_grants(Object(stdClass))
#6 /data/disk/o1/aegir/distro/015/profiles/hostmaster/modules/aegir/hosting/task/hosting_task.module(579): node_save(Object(stdClass))
#7 /data/disk/o1/aegir/distro/015/profiles/hostmaster/modules/aegir/hosting/task.hosting.inc(66): hosting_add_task('10614', 'verify', Array)
#8 [internal function]: drush_hosting_task_validate('@platform_custo...', 'verify')
#9 /data/disk/o1/tools/drush/includes/command.inc(422): call_user_func_array('drush_hosting_t...', Array)
#10 /data/disk/o1/tools/drush/includes/command.inc(231): _drush_invoke_hooks(Array, Array)
#11 [internal function]: drush_command('@platform_custo...', 'verify')
#12 /data/disk/o1/tools/drush/includes/command.inc(199): call_user_func_array('drush_command', Array)
#13 /data/disk/o1/tools/drush/lib/Drush/Boot/BaseBoot.php(67): drush_dispatch(Array)
#14 /data/disk/o1/tools/drush/includes/preflight.inc(66): Drush\Boot\BaseBoot->bootstrap_and_dispatch()
#15 /data/disk/o1/tools/drush/drush.php(12): drush_main()
#16 {main}

If you need any other information, please let me know. Thank you!