WSA only runs as Proxy not as Cache

kisanak_ironport · ‎10-08-2007

Press Ctrl-C to stop.
%CPU reqs client server %bw disk disk
used /sec hits misses kb/sec kb/sec saved wrs rds
83.16 9 0 92 997 997 0.0 0 0
87.11 83 0 838 7994 7994 0.0 0 0
82.82 86 0 864 8228 8228 0.0 0 0
83.30 99 0 995 8963 8963 0.0 0 0
83.56 89 0 897 7357 7357 0.0 0 0
82.88 81 0 818 6061 6061 0.0 0 0
82.83 68 0 681 6780 6780 0.0 0 1

Cache Hits:
Average in last minute 0
Maximum in last hour 0
Average in last hour 0
Maximum since proxy restart 6
Average since proxy restart 0

How to enable WSA also as Cache Server (beside as proxy server).

Thanks

jowolfer · ‎10-08-2007

kisanak,

The following option must be set:

'Security Services' tab > Web Proxy > Caching: Enabled

It is important to understand that the WSA will only cache objects that contain caching headers in the response.

Any objects that do not contain cache headers or contain negative cache headers, will not be cached.

moutaz_gawad_ironport · ‎09-18-2008

What you mean by cache header?

I have also the same problem on S650 5.5.2 OS

Does changing the caching to aggressive mode will solve this problem?

jowolfer · ‎09-19-2008

There are certain HTTP request / response headers that affect how object are cached.

Here are some of them:

Request headers:
Pragma: no-cache -Clients demands to not get the object from cache
cache-control: no-cache -same
cache-control: max-age=x -Only send an object if it has been cached for less then x seconds

Response headers:
cache-control: private -Do not cache this object
cache-control: max-age=x -Only cache for x amount of seconds

Aggressive caching will force the WSA to use cache more then it would typically. This may introduce issues with having stale content.

In this day and age, due to all of the dynamic content, it's not atypical for cache hit rates to be between 20-30%.