On 2021-06-28 21:18, Alessandro Motta wrote:> One thing that is still puzzling / worrying me: I completely failed to > identify the actual bottleneck when profiling the code. > > Did I simply misinterpret the profiling output / flame graph? Or is the > problem rather that memory allocations and garbage collection are not > tracked by the profiler?
Some things that might help (at least they helped me :-) ) ... - Use the `profile-thunk` function described at https://docs.racket-lang.org/profile/ (most likely that's how you got your profile data to begin with). - Use the `errortrace` option, i. e. run the instrumented program with `racket -l errortrace -t program.rkt`. The errortrace functionality is described as: When using Errortrace, profiles are more precise and more fine-grained (expression-level instead of function-level) but profiling has higher overhead and recompilation may be necessary. - Note the remark about recompilation. It took me a bit to realize that I had to delete the `.zo` files. :-) In practice, I remove the `compiled` folders for the program I want to run. If you don't remove the compiled code, the old code - without errortrace information - will be used, but as far as I remember you'll get no error message or warning. - There's also an option for the sample interval, so you can lower it to get finer-grained measurements. I don't find this now. Maybe someone else can point to more information. - Learn to read the text output of the profiler as described under https://docs.racket-lang.org/profile/#%28part._.Textual_.Rendering%29 Especially the distinction between the times with and without calls to nested functions is helpful. The profiler output may seem a bit overwhelming first, but with some time and experimentation it becomes better (like with so many things regarding Racket ;-) ). Stefan -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/08b4bcb1-145f-0824-55c0-05bf6641bf06%40sschwarzer.net.
