A description for this Performance-schema Table has not yet been added to this Documentation.
CREATE TABLE `mutex_instances` ( `NAME` varchar(128) NOT NULL COMMENT 'Instrument name associated with the mutex.', `OBJECT_INSTANCE_BEGIN` bigint(20) unsigned NOT NULL COMMENT 'Memory address of the instrumented mutex.', `LOCKED_BY_THREAD_ID` bigint(20) unsigned DEFAULT NULL COMMENT 'The THREAD_ID of the locking thread if a thread has a mutex locked, otherwise NULL.' )
Additional information on this topic may be found in the MariaDB Public Knowledge Base.
Information specific to MariaDB SkySQL can be found on the mutex_instances page in the SkySQL Documentation.