| The wait type LCK_M_S is ranked #11 by Stedman Solutions and Database Health Monitor. Wait statistics, in the context of SQL Server, refer to the amount of time that a query spends waiting to access data in the database. When a client application requests data from the database, the request is placed in a queue and the client application must wait for its turn to access the data. The time that the query spends waiting is called a "wait" and is tracked by SQL Server. This information can be used to identify potential performance bottlenecks and optimize the performance of the database. Wait statistics are commonly used by database administrators to diagnose and troubleshoot performance issues in SQL Server. In order to efficiently manage and retrieve data from a SQL Server database, the system uses a process called "waiting." When a client application requests data from the database, the request is placed in a queue and the client application must wait for its turn to access the data. One common wait type in SQL Server is the LCK_M_S wait type. This wait type occurs when a query is waiting to acquire a shared lock on a table in order to read or modify data. A shared lock allows multiple transactions to read or modify data in a table, but prevents other transactions from acquiring exclusive locks on the table. When a query encounters a LCK_M_S wait, it means that there is already a shared lock on the table that the query is trying to access, and the query must wait for the lock to be released before it can continue. This wait type can occur when multiple transactions are trying to access the same table simultaneously, or when a long-running transaction holds a shared lock on the table for an extended period of time. To minimize the occurrence of LCK_M_S waits, it is important to ensure that transactions are designed to acquire and release locks as quickly as possible. This can be achieved by using appropriate isolation levels, avoiding long-running transactions, and properly indexing tables to make data retrieval and modification more efficient. In summary, the LCK_M_S wait type in SQL Server occurs when a query is waiting to acquire a shared lock on a table in order to read or modify data. This wait type can be minimized by using appropriate isolation levels, avoiding long-running transactions, and properly indexing tables.
Applies toRelated WaitsLCK_M_BULCK_M_BU_ABORT_BLOCKERS LCK_M_BU_LOW_PRIORITY LCK_M_IS LCK_M_IS_ABORT_BLOCKERS LCK_M_IS_LOW_PRIORITY LCK_M_IU LCK_M_IU_ABORT_BLOCKERS LCK_M_IU_LOW_PRIORITY LCK_M_IX LCK_M_IX_ABORT_BLOCKERS LCK_M_IX_LOW_PRIORITY LCK_M_RIn_NL LCK_M_RIn_NL_ABORT_BLOCKERS LCK_M_RIn_NL_LOW_PRIORITY LCK_M_RIn_S LCK_M_RIn_S_ABORT_BLOCKERS LCK_M_RIn_S_LOW_PRIORITY LCK_M_RIn_U LCK_M_RIn_U_ABORT_BLOCKERS LCK_M_RIn_U_LOW_PRIORITY LCK_M_RIn_X LCK_M_RIn_X_ABORT_BLOCKERS LCK_M_RIn_X_LOW_PRIORITY LCK_M_RS_S LCK_M_RS_S_ABORT_BLOCKERS LCK_M_RS_S_LOW_PRIORITY LCK_M_RS_U LCK_M_RS_U_ABORT_BLOCKERS LCK_M_RS_U_LOW_PRIORITY LCK_M_RX_S LCK_M_RX_S_ABORT_BLOCKERS LCK_M_RX_S_LOW_PRIORITY LCK_M_RX_U LCK_M_RX_U_ABORT_BLOCKERS LCK_M_RX_U_LOW_PRIORITY LCK_M_RX_X LCK_M_RX_X_ABORT_BLOCKERS LCK_M_RX_X_LOW_PRIORITY LCK_M_S_ABORT_BLOCKERS LCK_M_S_LOW_PRIORITY LCK_M_SCH_M LCK_M_SCH_M_ABORT_BLOCKERS LCK_M_SCH_M_LOW_PRIORITY LCK_M_SCH_S LCK_M_SCH_S_ABORT_BLOCKERS LCK_M_SCH_S_LOW_PRIORITY LCK_M_SIU LCK_M_SIU_ABORT_BLOCKERS LCK_M_SIU_LOW_PRIORITY LCK_M_SIX LCK_M_SIX_ABORT_BLOCKERS LCK_M_SIX_LOW_PRIORITY LCK_M_U LCK_M_U_ABORT_BLOCKERS LCK_M_U_LOW_PRIORITY LCK_M_UIX LCK_M_UIX_ABORT_BLOCKERS LCK_M_UIX_LOW_PRIORITY LCK_M_X LCK_M_X_ABORT_BLOCKERS LCK_M_X_LOW_PRIORITY See AlsoAll Wait Types |  |
