I am working on GIS based web application using Mapnik and Tilecache with backend python. To display map in the browser, openlayers is used. Maps are generated by calling tilecache cgi url. I am facing a serious performance issue. Whenever I zoom or pan the map, a python process is called for rendering the tiles. It takes a certain amount of cpu space. When the map is zoomed or panned from more than one system, the cpu usage increases enormously resulting cpu hanging. I came to know about tilecache seeding process for precaching the tiles. As this application requires layer updation, this technique is somewhat insufficent for me. Also as there will be large number of systems accessing the server, this issue poses a big problem.
Another issue that I am facing is the shift in display of openlayers frame cloud while searching. In the map we display certain layers using images. While searching and displaying details through openlayers frame cloud, there is a spatial shift while frame cloud points to the item in the map. I tried several bbox extents and resolution but still that problem persists.
Please help in solving these issues. Thanks in advance.