There is an error in the documentation for the GRAPH_RESULT_LIFESPAN parameter. The documentation should read the following...
***GRAPH_RESULT_LIFESPAN***
Description: The number of minutes a cached graph result is valid.
Min value: 5
Max value: 60
*Possible Values: increments of 5*
Introduced in release: ALM 11.50
Introduced in patch: GA
System: false
So the default value is 60 which would update the graph every 60 minutes. When you add the Site Parameter if the value is set too low the parameter has no affect. Once you set the parameter value to an positive increment of 5 (ex. 5, 10, 15, 20) it will start working. Any graph public URLs that that were created before will not update until the current 60 minute cycle is complete and then after that they will update at the interval specified in the Site Parameter. Any new URLs created (graphs that you have never shared a URL previously) will update at the interval specified in the Site Parameter. To get graphs that were previously shared to update at the specified URL immediately you will have to go into Share Analysis Item and select **Reset Analysis Item Public URL** and then copy the public URL again.
***You may need to restart the ALM service to make the parameter changes take affect.***
Attached is a Micro Focus KB article that talks about this...[link text][1]
[1]: /storage/temp/823-the-parameter-graph-results-lifespan-is-not-updati.pdf