I have a published geoprocessing with view result as map serivce option.
My question is how long the result map service is still on the server, forever or after some time the result deleted?
That all depends on the cleanup time specified for ArcGIS Server to handle the results management. By default, the MaximumFileAge is 360 minutes (6 hours), but can be edited depending the the frequency and requirements of the Geoprocessing Service..
ArcGIS Help 10.1
Retrieving data ...