I have a map service with several global raster datasets. I'm using an ocean mask feature overlay to essentially clip the rasters (for display) to the world country outlines. The problem is that this overlay is causing pretty slow performance in the map. When I click on a raster it takes three or four seconds for the popup to come up and display the pixel value. Switching between rasters is also very slow. When I remove the overlay or hide it in the map service, I can instantly switch between the raster layers and the popup comes up immediately. It's a pretty drastic improvement. The trade off is that the map looks terrible with the rasters spilling out into the ocean. I've tried converting the shape to a raster, but the edges look blocky, even after bilinear interpolation. I can't save it as a basemap, because I can't publish basemaps to the server. I used the simplify tool to cut the shapefile size by two thirds, but this did not improve performance.
Has anyone else had a similar issue?