Beginning Microsoft SQL Server 2008 ... - S3 Tech Training

Shared Memory
Shared memory removes the need for inter-process marshaling — a way of packaging information before
transferring it across process boundaries — between the client and the server, if they are running on the
same box. The client has direct access to the same memory-mapped file where the server is storing data.
This removes a substantial amount of overhead and is very fast. It’s only useful when accessing the server
locally (say, from a Web server installed on the same server as the database), but it can be quite a boon
performance-wise.
On to the Client
Now we’ve seen all the possible protocols and we know how to choose which ones to offer. Once we
know what our server is offering, we can go and configure the client. Most of the time, the defaults are
going to work just fine, but let’s take a look at what we’ve got. Expand the Client Network Configuration
tree and select the Client Protocols node, as shown in Figure 2-4.
Figure 2-4
Chapter 2: Tools of the Trade
SQL Server has the ability for the client to start with one protocol, then, if that doesn’t work, move on to
another. In Figure 2-4, I am first using Shared Memory, then trying TCP/IP, and finally going to Named
Pipes if TCP/IP doesn’t work as defined by the Order column. Unless you change the default (changing
the priority by using the up and down arrows), Shared Memory is the NetLib that is used first for connections
to any server not listed in the aliases list (the next node under Client Network Configuration),
followed by TCP/IP and so on.
If you have TCP/IP support on your network, configure your server to use it for any
remote access. IP has less overhead and just plain runs faster; there is no reason not
to use it, unless your network doesn’t support it. It’s worth noting, however, that for
local servers (where the server is on the same physical system as the client), the
Shared Memory NetLib will be quicker, as you do not need to go through the network
stack to view your local SQL Server.
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