In the default IBM® HTTP Server for distributed
platforms configuration, the maximum fast cache accelerator dynamic
cache size is calculated as one-eighth of physical pin-able memory.
About this task
On a machine with 384 megabytes of RAM, a maximum of approximately
50 megabytes is available for the fast response cache accelerator
dynamic cache. When this limit is reached, the cache accelerator deletes
older entries to cache new entries.
Procedure
Using the IBM HTTP Server for distributed
platforms AfpaDynaCacheMax directive, tune the maximum-allowed cache
size: - Place the directive in the global server configuration
scope, along with the other default fast response cache accelerator
directives.
- Enable fast response cache accelerator. Enable
the fast cache accelerator by updating the following directives in
the IBM HTTP Server httpd.conf file:
AfpaEnable
AfpaCache on
AfpaLogFile "c:/Program Files/IBM HTTP Server/logs/afpalog" V-ECLF
AfpaDynaCacheMax 10
These settings limit the dynamic cache
size to 10 megabytes. If you use these directives to increase cache
size, do not make the cache so large that all of the physical memory
is consumed. Determine how much memory is available when all applications
are running, by using the Windows Task
Manager.
Assign no more than 50% of available physical memory
to the dynamic cache. Specifying too large a cache not only decreases
the performance of other applications, but also puts you at a risk
for completely running out of memory.
The default configuration
does not include the AfpaDynaCacheMax directive, where the cache size
is automatically calculated as one eighth of physical memory.