After running a short script several times without making changes (using include("script.jl"); from the REPL), I noticed that the number and total size of memory allocations was not constant. How (and why?) can this happen? I’ve attached the script and several samples of output for reference. start…

[image] mcmuffin6o: Putting everything into a module that gets reloaded each run is the only reliable way I’ve found to achieve deterministic program output in Julia. Otherwise, you get random crap based on whatever you last did at the REPL, since there’s no way to clear the workspace! Do you…

[image] mcmuffin6o: WARNING: replacing module HW6. This looks like you’re reincluding the file over and over again? In which case, it’s very possible that some runs include GC time where things that weren’t cleaned up before are cleaned up now. – I’ve moved this topic to General Usage, sinc…

Memory allocations does fluctuate for complex function calls, and IMO it’s a good question about internals. Here is the histogram for [@allocated Pkg.status() for _ in 1:50] [image] Which operation causes this variation? GC.enable(false) doesn’t change anything.

Putting everything into a module that gets reloaded each run is the only reliable way I’ve found to achieve deterministic program output in Julia. Otherwise, you get random crap based on whatever you last did at the REPL, since there’s no way to clear the workspace! As a side note, if I tried to re…

[image] mcmuffin6o: As a side note, if I tried to recommend Julia in its current state to a bunch of MATLAB junkies, I’d get laughed out of the room as soon as they ask about whether or not it’s possible to do something as trivial as clearing the workspace. MATLAB’s clear / clearvars is made fe…

The last link you provided explains it all: Advanced MATLAB users tend to write functions, not scripts. The average MATLAB junkie doesn’t. The average MATLAB junkie has no idea what you’re talking about. As a side note, I have tried working from the REPL several times. It’s never as good as run…

Your way of using Modules does not mesh with Revise: Revise.jl doesn’t go into the module you want to develop, instead it should be used from the REPL. You should not put a function call like main() inside a module and then re-include that module for the sake of running main. One way to correctly…

I’d also note that if you wrap everything in functions, like you did there, wrapping everything in the module is not necessary. Using Revise, includet and just calling the functions with appropriate input is enough.

What if I am editing a function in another module that I’m using? There have been multiple instances where I’ve edited a function in another module only for the code to call the old definition of the function because I’ve changed the call signature or the types within the call signature. It stopped…

Is there any reason not to do it the way that I’ve done it? I don’t really care about how it should be done; I just care that it works.

Reincluding modules gives a WARNING and those are usually added for a reason. But I don’t know what problems that can cause. Also: using Revise in your script will have not effect, you can essentially uninstall it.

Non-Deterministic Memory Allocation?

General Usage

dlakelan October 21, 2023, 1:17am 16

If you really want to reset everything also you can call exec (in Linux at least).

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Non-Deterministic Memory Allocation?

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