Page 1 of 1

Monte Carlo analysis stopped

Posted: 18 Feb 2016 16:36
by romains
Dear OpenLCA community,

after 10 days of Monte Carlo analysis (4100 iterations out of 5000), OpenLCA suddenly disappeared from the screen.

The Windows task manager still shows openLCA.exe as running and using CPU and RAM, but OpenLCA disappeared.
Has anyone encountered this issue?

Best regards,
Romain

Re: Monte Carlo analysis stopped

Posted: 20 Feb 2016 12:49
by aciroth
Ah, sorry to hear. There is an inconvenient bug on the current version of openLCA, for every simulation step, a full analysis is performed which is relatively slow, and consumes much more memory than necessary. We will correct this in the upcoming version 1.5 (planned to be released as first beta next week). In your case, I would kill the still running openLCA process. Reason for the disappearance can be "reawaking" from power safe mode, or memory issues. If you cannot wait until the public release, let me know, we can share the intermediate test version (alpha 7, so reasonably stable in our tests).
Best wishes,
Andreas

Re: Monte Carlo analysis stopped

Posted: 22 Feb 2016 15:27
by romains
Hello Andreas,

thanks for the heads-up. Ok, I understand.
So, I chose not to kill it, hoping the window would pop up at the end of the 5000 iterations, but did not.
It just disappeared from the task manager, silently.

No, it's fine, I can wait for the public release, but I am extremeley looking forward to it :-)
I'll just do my scenario analyses in the meanwhile.

Best regards,
Romain

Re: Monte Carlo analysis stopped

Posted: 02 Apr 2016 11:46
by mptsang
Hello,

I am curious about the length of time it takes to run MC Simulations in openLCA. I tested a few trial-runs of 100 iterations and it was tremendously slow (1+hour), and now when I see that it took someone 10 days to reach 5000 iterations I am not certain I want to use openLCA for this.

Is this length of time normal? Is there a way to speed up the MC Simulations (e.g. allocating more memory to the application)?

Lastly, is it possible to run the MC Simulations for all impact categories at the same time? By default it seems it is only possible one impact category at a time.

Best,

Michael

Re: Monte Carlo analysis stopped

Posted: 03 Apr 2016 17:45
by aciroth
It was really slow for the released 1.4 version because of a bug (we always performed a full analysis for each step) but it is now again much faster, in the 1.5 beta release. Therefore please check this release for Monte Carlo simulations.

Re: Monte Carlo analysis stopped

Posted: 05 Apr 2016 10:19
by mptsang
Hi Andreas,

Indeed, I have seen the slow MC-simulations on both 1.4 and 1.5 (as I recently installed and tested my datasets on the newest version just released). Have you and your team successfully ran MC-simulations yet running 1.5?

(And, in general, I am noticing the same slower work-speeds in 1.5 that occurred in 1.4 when working with the Ecoinvent 3 inventory.)

Best,

Michael