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LSAM CONFIGURABLE CACHE REPLACEMENT POLICIES
============================================
LSAM Authors: Amy Hughes, Lars Eggert
$Revision: 1.9 $ ($Date: 1998/07/02 23:42:41 $)
More Information: http://www.isi.edu/lsam/dynamic-cache


Introduction
------------
The LSAM Proxy suports several different cache replacement algorithms.  The
choice of algorithm can be specified in the httpd.conf configuration file and
is static.  This allows the proxy administrator to select an algorithm
appropriate to the use of the server.

The default Apache algorithm replaces files based on their expire times, the
files closest to expiring will be removed first.  The new algorithms that have
been added include: FIFO, LRU, file size replacement (replace large or small
files first), and download- time replacement (replace the files with the
longest or shortest download time first).

The proxy also supports a partitioned cache.  Each channel that is received by
the proxy will store its files in a separate partition.  The same garbage
collection algorithm, as described above, will be used for all partitions.


Demonstration
-------------
1. Start two proxies.  
2. Tune in the same channel on each proxy.
   (Choose "Channel Management" from the Configuration web page)
3. Use one proxy to request files from that channel.
4. View the channel partition on the second proxy to view the 
   files that are now in the channel partition.


Upcoming Features
-----------------
* The ability to use different caching algorithms for different partitions.