Sergei Petrunia added a comment - 2018-11-29 19:28 It's the same in Percona Server mysql> select * from information_schema.processlist\G *************************** 1. row *************************** ID: 3 USER: root HOST: localhost DB: test COMMAND: Query TIME: 6 STATE: statistics INFO: select * from t10 where pk=2 for update TIME_MS: 6724 ROWS_SENT: 0 ROWS_EXAMINED: 0

Sergei Petrunia added a comment - 2019-01-03 19:23 Well, one can observe TokuDB lock waits with tokudb_lock_waits table: MariaDB [j1]> select * from information_schema.TokuDB_lock_waits\G *************************** 1. row *************************** requesting_trx_id: 95 blocking_trx_id: 93 lock_waits_dname: ./j1/t10-main lock_waits_key_left: ff01000000 lock_waits_key_right: 0101000000 lock_waits_start_time: 1546543046850 lock_waits_table_schema: j1 lock_waits_table_name: t10 lock_waits_table_dictionary_name: main There is also TokuDB_trx table which maps Toku's transaction id to mysql connection id: MariaDB [j1]> select * from information_schema.TokuDB_trx\G *************************** 1. row *************************** trx_id: 93 trx_mysql_thread_id: 10 trx_time: 435 *************************** 2. row *************************** trx_id: 95 trx_mysql_thread_id: 11 trx_time: 314 2 rows in set (0.002 sec)