Wait Type PAGELATCH_SH

The wait type PAGELATCH_SH is ranked #22 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.


SQL Server PAGELATCH_SH wait types occur when a transaction is waiting for a shared (read) latch on a page in a database file. Latches are lightweight locks that are used to protect internal data structures in a database, and they are typically held for very short periods of time.

When a transaction needs to read data from a page in a database file, it first checks to see if there are any existing latches on that page. If there are no latches, the transaction can proceed with the read. If there are existing latches, however, the transaction must wait for those latches to be released before it can read the data.

This waiting period can cause performance issues if it lasts for too long. To avoid these issues, it is important to monitor your SQL Server for PAGELATCH_SH wait types and take steps to reduce the amount of time that transactions spend waiting for latches.

One way to do this is to make sure that your transactions acquire and release latches as quickly as possible. This can be accomplished by using the right isolation level for your transactions and by ensuring that your transactions are short and to the point.

Another way to reduce the amount of time that transactions spend waiting for latches is to optimize the way that data is accessed in your database. This can be done by using the right indexing strategy and by properly organizing the data in your database files.

Overall, SQL Server PAGELATCH_SH wait types can be a sign of potential performance issues in your database. By monitoring for these wait types and taking steps to reduce the amount of time that transactions spend waiting for latches, you can improve the performance of your SQL Server and ensure that your database runs smoothly.

Applies to

Related Waits

PAGELATCH_DT
PAGELATCH_EX
PAGELATCH_KP
PAGELATCH_NL
PAGELATCH_UP

See Also


All Wait Types