wait/io/file

一个已插装的文件 I/O 操作。对于文件来说，等待时间是指等待文件操作完成的时间（例如，调用 fwrite()）。由于缓存的原因，磁盘上的实际文件 I/O 可能不会在此调用中发生。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.

wait/io/socket

一个已插装的套接字操作。套接字插装器的名称格式为 wait/io/socket/sql/socket_type。服务器为其支持的每种网络协议都有一个监听套接字。与 TCP/IP 或 Unix 套接字文件连接的监听套接字相关联的插装器，其 socket_type 值分别为 server_tcpip_socket 或 server_unix_socket。当监听套接字检测到连接时，服务器将该连接转移到由单独线程管理的新套接字。新连接线程的插装器的 socket_type 值为 client_connection。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.

wait/io/table

一个带有监测的表 I/O 操作。这些操作包括对持久性基础表或临时表的行级访问。影响行的操作有提取、插入、更新和删除。对于视图，等待与视图引用的基础表相关联。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.

与大多数等待不同，表 I/O 等待可以包含其他等待。例如，表 I/O 可能包括文件 I/O 或内存操作。因此，events_waits_current 中的表 I/O 等待通常有两行。有关更多信息，请参见 第 29.8 节，“性能模式原子和分子事件”。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 29.8, “Performance Schema Atom and Molecule Events”.

某些行操作可能会导致多次表 I/O 等待。例如，插入操作可能会触发导致更新的触发器。Some row operations might cause multiple table I/O waits. For example, an insert might activate a trigger that causes an update.

wait/lock/table

一个带有监控的表锁操作。An instrumented table lock operation.

wait/lock/metadata/sql/mdl

一个带有监控的元数据锁操作。An instrumented metadata lock operation.

wait/synch/cond

条件用于让一个线程向其他线程发出信号，表示它们正在等待的某件事情已经发生。如果只有一个线程在等待条件，它可以被唤醒并继续执行。如果有多个线程在等待，它们都可以被唤醒并竞争它们所等待的资源。A condition is used by one thread to signal to other threads that something they were waiting for has happened. If a single thread was waiting for a condition, it can wake up and proceed with its execution. If several threads were waiting, they can all wake up and compete for the resource for which they were waiting.

wait/synch/mutex

互斥对象用于允许访问资源（例如一段可执行代码）同时防止其他线程访问该资源。A mutual exclusion object used to permit access to a resource (such as a section of executable code) while preventing other threads from accessing the resource.

wait/synch/prlock

一个优先级读写锁对象。A priority rwlock lock object.

wait/synch/rwlock

一个普通的读/写锁对象，用于锁定特定变量以便访问，同时防止其他线程使用它。共享读锁可以被多个线程同时获取。排他写锁一次只能被一个线程获取。A plain read/write lock object used to lock a specific variable for access while preventing its use by other threads. A shared read lock can be acquired simultaneously by multiple threads. An exclusive write lock can be acquired by only one thread at a time.

wait/synch/sxlock

共享-排他（SX）锁是一种读/写锁对象，它在允许其他线程进行不一致读取的同时提供对公共资源的写访问。sxlocks优化并发性并提高读写工作负载的可扩展性。A shared-exclusive (SX) lock is a type of rwlock lock object that provides write access to a common resource while permitting inconsistent reads by other threads. sxlocks optimize concurrency and improve scalability for read-write workloads.