I've been using ruby-prof's memory profiling mode to try to reduce the memory usage of an app, with ruby enterprise edition and rails 2.2.2. I setup a profiling test (as recommended in the ruby-prof docs) for a single action, and after my refactoring ruby-prof said I had cut memory usage by 1/3 and object allocations by 1/2. After this, I setup a script to hit that action repeatedly with the same parameters and measure the amount of memory used by the mongrel process, once for my refactored code and once for point I branched from. This script tells me that I've actually made the memory usage worse by about 10-20%. Has anyone run into a discrepancy like this before?
on 2009-02-04 21:22