I have an mvc4 web api that services on average (W3SVC_W3WP) 50req/sec (per each server) on 4 physical servers (xeon 2.5Ghz 6 core 12 logical processors with 64G memory running win2008R2 64bit).
Recently we started to get flooded with new request due with poor capacity planning and we are seeing lots of queuing (asp.net v4.0.30319 Requests Queued = 2k-5k) and total req/sec up to about 200 (avg before was 50 that we could handle).
What can I do do help scale my application on each of the four servers?
Here is a link to some perf counters -> http://bit.ly/WHFNv0
**Given**:
- IIs 7.5 - 2 web sites (both expose web rest api) running on one 64bit integrated app pool
- cpu per server ~45-55%
- One worker process (w3wp.exe)
- Queue Length = 1000
**MachineConfig:**
<system.web>
<processModel autoConfig="false" maxWorkerThreads="4095" maxIoThreads="4095" minIoThreads="2047"
requestQueueLimit="5000" responseDeadlockInterval="00:03:00" />
<httpRuntime minFreeThreads="704" minLocalRequestFreeThreads="608" />
</system.web>
Setting max worker processes in IIS Advanced Pool Settings from 1 -> 2 didn't seem like it helped much.