Microsoft® SQL Server 2008 R2 Unleashed

Minimizing Locking Contention

Although setting the lock timeout prevents a process from waiting indefinitely for a lock request to be granted, it doesn’t address the cause of the locking contention. In an effort to maximize concurrency and application performance, you should minimize locking contention between processes as much as possible. Some general guidelines to follow to minimize locking contention include the following:

• Keep transactions as short and concise as possible. The shorter the period of time locks are held, the less chance for lock contention. Keep commands that are not essential to the unit of work being managed by the transaction (for example, assignment selects, retrieval of updated or inserted rows) outside the transaction. ...