A database exists as a read-intensive server that is operating with query_cachek_type = DEMAND.
The database is refreshed periodically, but the resultset size of the queries does not fluctuate.
Note the following details about this environment:
✑ A web application uses a limited set of queries.
✑ The Query Cache hit rate is high.
✑ All resultsets fit into the Query Cache.
✑ All queries are configured to use the Query Cache successfully.
The response times for queries have recently started to increase. The cause for this has correctly been identified as the increase in the number of concurrent users accessing the web service.
Based solely on the information provided, what is the most likely cause for this slowdown at the database level?