Optimizing Web application showing a worklist via hibernate and 2nd level cache (ehcache, etc)

We have an application that is receiving constant queries for a 'worklist' which consists of frequently updated data which is populated in the db by a SOA background process. Thousands of users have this worklist open in a browser on an automatic 30-60sec refresh. We are evaluating the use of Hibernate with a 2nd level cache to reduce load on the Oracle 10RAC db.

The concern is that the worklist needs to display a highly up to date view of the user's outstanding work. Is this a viable situation to solve with ehcache or will cache hit rate be too low? Also the cache would either have to throw out d开发者_开发问答ata after a brief period or the SOA background process would have to update it constantly.

Thoughts?

@Innovate: generally cache is used when application requires to serve same data for more than one request...in ur case, if your data changes very frequently, it is very likely that cache will contain stale data and it will need DB hit to refresh itself...another way of optimizing your solution since you are using hibernate, is use concept of batch fetching if possible which will load data for multiple users in one go and hence will reduce load on oracle.