User manual

Chapter 2: Setting up the CacheRaQ 4
22 Cobalt CacheRaQ 4 User Manual
Document Maximum Time Before Expiration
This setting specifies the maximum amount of time (in hours) that a document
remains in the cache before it expires. This value is used in conjunction with the
value for the document expiration age fraction. A cached document expires by
the earlier of the two methods: document expiration age fraction or maximum
time before expiration.
Maximum Size of Cacheable Documents
This setting specifies the maximum size (in MB) for a cached document. It can
prevent a very large document from evicting several small documents from the
cache. A large value (for example, 20MB) is a good setting — very large
documents (for example, multimedia files) can often be cached at this setting.
Disk Space for Log Files
This setting controls the amount of disk space (in MB) on the CacheRaQ 4 that is
devoted to storing log files. One log file is generated each day and is used to
generate the information in the Cache Statistics section of the UI.
It is recommended to enter a large value (up to one thousand MB [one GB]) in
this field, enough for a one or two months of log files. If users on your network
generate heavy HTTP traffic, increase this setting.
Disk Space for Usage Statistics
This setting controls the amount of disk space (in MB) dedicated to the per-client
and per-server usage information that is calculated nightly. These statistics are
described in more detail in the next chapter.
Cache Proxy Settings table
Enable Cache Look-ahead
This check box enables the “look-ahead” feature on the CacheRaQ 4. As the
CacheRaQ 4 pulls in a Web page that a client machine has requested, it also
examines the HTML code for other objects referenced from the same Web server
(for example, image files). If the CacheRaQ 4 finds any objects, it requests them
as well. If a user’s browser subsequently requests these objects, the CacheRaQ 4
returns the pre-cached objects.