I am running SQL Server 2008 R2 (64-bit) standard on a Windows 2008 64-bit server. I typically notice during work hours that our "baseline" Batch Requests/Sec will fall in the 200-500 range. Lately I've noticed that we've had spikes that consistently fall in the 1500-2000 range for about 2-3 minutes where it will then level off again to the 200-500 range. This morning I actually noticed a brief spike to 3000-4000, then dipping to the 1500-2000, and now currently back intot he 200-500 range.
When the batch requests/sec spikes the CPU usage does increase, but not much. Most of the time the CPU never gets about 20% usage for the sqlserver process. There doesn't seem to be any performance issues when these batch/req increases happen, but I would still like to know how I can find what is causing them.
I have run some queries on sys.dm_exec_sessions and sys.dm_exec_connections but don't see anything abnormal when comparing low batch/sec periods vs high batch/sec periods. I would appreciate any input to find out where all of these requests are coming from. Thanks.