SQL Server manages the acquiring and releasing of table locks by using an internal hash table with 101 rows (known as hash buckets) and of page and address locks by using internal hash tables with 1031 rows each. In release 11.0, these tables use one or more spinlocks to serialize access between processes that are running on different engines. A spinlock is an internal locking mechanism that prevents a second process from accessing the resource currently being used by another process. All processes trying to access the resource must wait (or spin) until the lock is released.
For SQL Servers running with multiple engines, you can set the ratio of spinlocks protecting each hash table using the table lock spinlock ratio, page lock spinlock ratio, and address lock spinlock ratio configuration parameters. The table locks hash table default ratio is 20 rows for each spinlock, and the page or address locks hash table default ratio is 100 rows for each spinlock. A SQL Server configured with only one engine has only one spinlock for each hash table, regardless of the values specified for these parameters.
For information about configuring the table lock spinlock ratio, page lock spinlock ratio, and address lock spinlock ratio parameters, see Chapter 11, “Setting Configuration Parameters,” in the System Administration Guide.
