Thread Instrument Elements Instrumented threads are displayed in the  setup_threads  table, which exposes thread class names and attributes. Thread instruments begin with  thread  (for example,  thread/sql/parser_service  or  thread/ performance_schema/setup ). An instrumented I/O operation. An instrumented file I/O operation. For files, the wait is the time waiting for the file operation to complete (for example, a call to  fwrite() ). Due to caching, the physical file I/O on the disk might not happen within this call. An instrumented socket operation. Socket instruments have names of the form  wait/io/socket/ sql/ socket_type . The server has a listening socket for each network protocol that it supports. The instruments associated with listening sockets for TCP/IP or Unix socket file connections have a socket_type  value of  server_tcpip_socket  or  server_unix_socket , respectively. When a listening socket detects a connection, the server transfers the connection to a new socket managed by a separate thread. The instrument for the new connection thread has a  socket_type  value of client_connection . An instrumented table I/O operation. These include row-level accesses to persistent base tables or temporary tables. Operations that affect rows are fetch, insert, update, and delete. For a view, waits are associated with base tables referenced by the view. Unlike most waits, a table I/O wait can include other waits. For example, table I/O might include file I/O or memory operations. Thus,  events_waits_current  for a table I/O wait usually has two rows. For more information, see Section 27.8, “Performance Schema Atom and Molecule Events” . Some row operations might cause multiple table I/O waits. For example, an insert might activate a trigger that causes an update. An instrumented lock operation. An instrumented table lock operation. • wait/lock/metadata/sql/mdl • wait/lock/table • wait/lock • wait/io/table • wait/io/socket • wait/io/file • wait/io 4927 • statement/sql : An instrumented SQL statement operation. For example, the  statement/sql/ create_db  and  statement/sql/select  instruments are used for  CREATE DATABASE  and  SELECT statements. Thread Instrument Elements Wait Instrument Elements