Microsoft Office Tutorials and References
In Depth Information
Optimizing for Performance
When you’re load balancing multiple WFEs, you can choose between hardware and software load
balancers. This might impact the performance as well.
A firewall is normally a requirement when you’re using the server in extranet scenarios, but it will slow
down the communications. For extranet scenarios, the speed outside your internal network is much
slower. Excel Services does not have a mode in which it sends smaller amounts of information for low
You can configure IIS to use HTTP compression to reduce the size of the information sent over the wire.
This is a tradeoff between CPU and network — enabling this setting will reduce the usage of the network
resources, but it will require certain CPU usage (both on the server machine and the client machine) to
compress and decompress the transmissions.
Connection Between the Office SharePoint Server Machines
In most topologies, the WFE, application server and database server machines are connected with a
high-speed local network. You can ensure that the appropriate network speeds and network cards are
used to connect the machines in the farm.
In some topologies, a firewall should be deployed between the WFE machines on one side, and the
application server and database server machines on the other side to further protect the access to the workbook
content. In addition, the administrator can require secure connections between the WFE and the ECS. As
with the connections to the WFE, your specific needs should determine the right balance between security
The communication between the WFE and the ECS is through web service calls. These use TCP/IP ports
that are freed after a certain timeout. To ensure that you do not run out of available ports on systems that
perform a high amount of requests, you might need to increase the value of the following registry key on
the WFE machines: HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters .
Downloading files over the network from their storage location might be a significant performance hit.
Excel Services uses a local cache to minimize additional downloads after the initial one. The ECS accesses
the file storage location to check that the file has not changed, and that the user has permissions to
access the file for every new session, even when the file is in the cache. If the file storage is in an
external location (such as a UNC share or web folder), make sure that the storage is fast enough and does
not become a bottleneck. For some very specific solutions that require a limited set of workbooks that
do not change often, consider deploying the files locally to each ECS machine. The administrator can
set the maximum workbook size setting to prevent extremely large files from affecting the overall
performance of the server.
Connection with External Machines
Additional machines outside the farm are involved in some of the requests, especially the ones related to
querying for external data. For example, to refresh a pivot table, the following servers might be accessed:
the database that contains the data, the SSO server for getting credentials, the SharePoint database server
for loading the connection information from a data connection library, and the active directory for certain
credential types. Optimizing external data queries is a complex topic, and it is explained in detail in