This Database warning occurs 69 times in all mediawiki-extensions-hhvm builds for extensions unrelated to Flow
Mon Jun 8 13:49:36 UTC 2015 integration-slave-trusty-1013 jenkins_u0_mw-unittest_ Flow\Repository\TreeRepository::insert localhost 1137 Can't reopen table: 'unittest_flow_tree_node' (localhost) INSERT INTO unittest_flow_tree_node (tree_descendant_id,tree_ancestor_id,tree_depth) SELECT '#«‰\"à(·yü€',tree_ancestor_id,tree_depth + 1 FROM unittest_flow_tree_node WHERE tree_descendant_id = '#÷Æ&ÑÁ#qh'
Mon Jun 8 13:49:39 UTC 2015 integration-slave-trusty-1013 jenkins_u0_mw-unittest_ Flow\Repository\TreeRepository::insert localhost 1137 Can't reopen table: 'unittest_flow_tree_node' (localhost) INSERT INTO unittest_flow_tree_node (tree_descendant_id,tree_ancestor_id,tree_depth) SELECT '7M¼%ÓÕ¿»Uê',tree_ancestor_id,tree_depth + 1 FROM unittest_flow_tree_node WHERE tree_descendant_id = '7M¼%ËÕ¿»Uê'
Most've been recently introduced because our logs were almost empty a week ago.