User manual

Chapter 3 Managing Websites 39
3 In the Sites pane, double-click the site in the list.
4 In the Options pane, click Performance Cache to change its state.
5 Click Save.
You can also improve server performance by disabling the access log.
Interaction Between the Performance Cache and Apache
The Apache web server uses port 16080 when the performance cache is enabled.
Blocking this port could interfere with web service. In previous versions of Mac OS X
Server it was necessary to keep this port open in the firewall, because server
redirection caused the port number to be appended to the URLs used by web
browsers.
The performance cache communicates on port 80, which is normally used for Web
service. Each port can accommodate only one service. Since the performance cache
process is a front-end http server by itself, Apache is reconfigured to run on port 16080.
That is, when the performance cache is on, Apache adds 1600 to the port number.
Performance cache is enabled by default.
The performance cache stores data that can be reserved to clients who request it
again. However, not all data can be cached. In this case, the performance cache
retrieves the data by querying the Apache server locally on port 16080. You may
sometimes see clients sending requests to port 16080 directly, as the result of a redirect
sent to the clients by the server. Otherwise the performance cache process should
transmit all request-response cycles.
Note: Because of this design, the performance cache process introduces a small
performance penalty when serving dynamic content.
Enabling Access and Error Logs for a Website
You can set up error and access logs for individual websites that you host on your
server. However, enabling the logs can slow server performance.
To enable access and error logs for a website:
1 In Server Admin, click Web in the list for the server you want.
2 Click Settings in the button bar.
3 In the Sites pane, double-click the site in the list.
4 In the Logging pane, check Enable Access Log to enable this log.
5 Set how often you want the logs to be archived by clicking the checkbox and typing a
number of days.
6 Type the path to the folder where you want to store the logs.
You can also click the Browse button to locate the folder you want to use.