Re: Octave suddenly running scripts slowly after crash

[Markus Mützel]

> Date: Tue, 11 Dec 2018 18:25:43 +0000
> From: Eric Kastanis <address@hidden>
> To: "address@hidden" <address@hidden>
> Subject: Octave suddenly running scripts slowly after crash
> Message-ID:
>       <address@hidden>
>       
> Content-Type: text/plain; charset="iso-8859-1"
> 
> Hello,
> 
> I am running Octave 4.4.1 x64 on a Dell Precision 7520 (Core i7-7820HQ @ 2.9 
> GHz, 16 GB RAM) with Windows 10 Pro, which I installed from the binary 
> provided on the GNU FTP site. I have been running a simple physical model 
> that consists of solving a non-stiff non-linear ODE, using a explicit 
> numerical scheme in a for loop. I've been running the model multiple times 
> while changing model parameters in order to fit the solution to some test 
> data I have. The script takes just a couple seconds to run, so it was 
> expedient to run it multiple times to heuristically estimate the model 
> parameter values.
> 
> Octave is very buggy on my PC, and crashes often. Usually I just restart it 
> and carry on. Yesterday after a crash, I reopened Octave and tried to run the 
> model again. At first I thought it was hung up, but it turns out the model 
> execution time had just increased by an order of magnitude or more. I checked 
> some other data processing scripts that I've created in the past that used to 
> run very quickly, and they are also now running very slowly, to the point 
> where they are too slow to be useable.
> 
> I can run my model in MATLAB and it still takes just a second or so. I used 
> 'profile' in Octave to see where the hang-up might be, and the sum of all the 
> function executions is less than a second, whereas the difference between the 
> tic and toc at the beginning and end of the file is ~25 s.
> 
> I've reinstalled Octave, tried different versions, and I'm at a bit of a loss 
> now. I've tried searching for others' experience with similar problems and 
> haven't come up with anything. Any advice or input would be very much 
> appreciated.


It's strange that Octave would run slower after a crash.

Just some wild guesses:
Is it possible you ran the test before the crash with your laptop connected to 
mains, and after the crash on battery? It might be related to Windows' 
performance settings.
Possibly, some kind of compatibility mode was activated: Find the file 
"octave-gui.exe" in "C:\Octave\Octave-4.4.1\bin" and check the compatibility 
tab in its properties.
It might also be related to your antivirus software which might have decided to 
sandbox Octave.

I hope this can help in tracking down the issue...

Markus