Do you think it's a good idea to use more metrics than just average frame rate when testing render performance? I mean 95th percentile, minimium frame rate, etc.
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Posted 23 March 2013 - 01:47 PM
Yeah average framerate alone definitely isn't enough. You really want a graph of frame times (don't use FPS, it's non-linear) so that you can clearly see if there's any spikes, fluctuations, or stuttering. A highly variable frame time results in a very bad playing experience, even if the average frame rate is still "high". So a game that's locked at a constant 33.3ms (30fps) will often be perceived as "smoother' than a game that averages close to 16.6ms (60fps) but fluctuates from frame to frame.
Edited by MJP, 24 March 2013 - 12:28 AM.
Posted 23 March 2013 - 01:50 PM
Profiling helps identify bottlenecks, when looking to optimize. Profilers tell you the average amount of time a function takes, and even more importantly, the number of times it is called during a specific program run. Saving 10ms on a function that is only called 20 times a frame isn't as good as saving 1 ms on a function that is called two hundred thousand times a frame.
Edited by Servant of the Lord, 23 March 2013 - 01:53 PM.
It's perfectly fine to abbreviate my username to 'Servant' rather than copy+pasting it all the time.
All glory be to the Man at the right hand... On David's throne the King will reign, and the Government will rest upon His shoulders. All the earth will see the salvation of God. [Need free cloud storage? I personally like DropBox]
Posted 23 March 2013 - 09:47 PM
Posted 30 March 2013 - 12:01 AM
Speaking of profiling and performance tracking, riting your own lightweight profiler is a great way to keep on top of how different bits of your game are performing. You set it to run per-frame and record timings for various bits of code. This is valuable for knowing where to look when you get performance drops during development - you might think the hit may be coming from what you're working on, but another part of the code has been affected.
A good example/tutorial is here:
I wrap certain functions up (culling, physics update, particles update, game code update, rendering, etc etc) in a profiling event and output a colour coded graph so I can quickly see what's going on. No where near as fine grained as a proper profiler but I feel it's much more useful!