INF: Memory Overhead for Connections, Objects, Locks, and DBs in SQL Server 6.x (160234)

MORE INFORMATION

SQL Server 6.0:

   Parameter               Value
   ----------------------------------------------------------------
   User connections        44 KB per user (approximately -- see below)
   Locks                   52 bytes per lock
   Open objects           224 bytes per object
   Open databases          20 bytes, plus 160 bytes per database
				

SQL Server 6.5:

   Parameter               Value
   ---------------------------------------------------------------
   User connections        44 KB per user (approximately -- see below)
   Locks                   60 bytes per lock
   Open objects           240 bytes per object
   Open databases       1,144 bytes, plus 160 bytes per database
				

User connection overhead is made up of a fixed amount of memory (18 KB) allocated per connection, plus memory allocated to structures supporting the connection within SQL Server and Windows NT Server. This value depends on the number of connections, the number of shared threads, and other structures allocated. Empirical testing has shown that this dynamic overhead is approximately 26 KB per user connection, giving a total of 44 KB per connection. This applies up to the worker thread limit; at this point the connections begin sharing threads, and the overhead per connection is reduced.