Intermittent Slow Response From Geoprocessing Service

[JohnSterritt1]

We are trying to track down performance issues with a GP services being accessed through the REST environment on Server 2008, IIS 7.5, ArcGIS Server 10 SP 3. In our testing the using Fiddler and Chrome Developer Tools we have determined the request is received quickly through the network, but the server is slow to send the response back to the client. In watching the performance monitor we can see the CPU usage spike when the Python processing is being executed, and messages returned from the Geoprocessing service indicate the geoprocessing is happening at a consistent rate. When the performance is high the response is received within 3-4 seconds, when it's slow it can take upwards of 1-2 minutes for the same request. Performance can change over subsequent runs 1-2 seconds followed by a 1-2 minute run. When are running a json recordset as input to the gp service, and receiving a featureset back. All testing is currently being done within the web interface automatically created  server http://<task-url>/execute.

Using Appcmd on the server it has been noticed that the application is hanging in the ResolveRequestCache state.

Any help or suggestions on resolving this issue would be greatly appreciated.

[RaviNarayanan]

Hi John,
Can you please contact ESRI Support regarding this question? This might require some troubleshooting and it will be better to work with Support in reproducing the issue in-house for troubleshooting.

[JohnSterritt1]

Hi Ravi,

We had a support ticket open with ESRI Canada, but couldn't reproduce the issue. We believe the issue is likely related to the servers configuration. Testing on two identical physical servers the issue is easily reproducible. We also setup a third server in a virtual environment and cannot reproduce the issues. We are currently trying to track down the issue on the physical boxes. We enabled Failed Request Tracing in IIS with a 20 sec connection timeout. The tracing again indicates that the process is getting hung-up on the ResolveRequestCache. Other than rebuilding the physical machines we are running out of things to try.

[MichaelStranovsky]

Were you able to resolve this?  We are experiencing a similar situation.  We were running a Geoprocessing Service on a ArcGIS 9.3.1 server.  Once we upgraded to ArcGIS 10 with SQL Server 2008, we experienced a significant slowness in the response.