cache application block expiration on a webfarm

[Felix Planjer]

Hi group,

We're developing an application that may be migrated to a web farm in
the future, but we want to be prepared for the move, hence the following
question:

Using the Caching Application Block, how can one machine, when updating
a table in the database, signal it's own, but more importantly, signal
the other machines cache to invalidate the cached database result?

Regards, Felix

 

[bruce barker]

it depends on how out of date the cache can be. if you can afford a lag,
then a notification of cache invalidation can be sent. you could use udp for
this, a database table you poll, sqlserver notification services. etc.

if no lag is allowed, then you will will have to implement a distributed
lock manager, as you must lock the cache on all servers during updates, and
invalidate after. if you do not understand coding a dlm, (microsoft havesn't
yet for their cluster support), then you probably should abanon the local
cache, and use sqlserver for the cache - it will be faster.

-- bruce (sqlwork.com)



| Hi group,
|
| We're developing an application that may be migrated to a web farm in
| the future, but we want to be prepared for the move, hence the following
| question:
|
| Using the Caching Application Block, how can one machine, when updating
| a table in the database, signal it's own, but more importantly, signal
| the other machines cache to invalidate the cached database result?
|
| Regards, Felix