[Scilab-users] Xcos 6.1.0 - benchmark time test

[Clément David]

Hello Pierre,

Thanks for the numbers, I will try to describe what can be down to work around the time to results.

>From when you start the simulation to the first scope popup, the schema is converted to a list of functions to be called in a specific order and passed to a solver that will iterate on time to "run" the simulation. There might be a difference between Scilab 5 and Scilab 6 as this transformation is written using the Scilab language. It is the 5s to 95s ratio.

While the simulation is running, each block's simulation function is called a number of times. The solver/simulator/function API did not change between Scilab 5 and Scilab 6, this should perform the same way. However, some functions, especially sciblk2 and sciblk4 are  wrappers from C to Scilab functions and have been re-written to behave very differently. It is the 253s (258-5) to 4258s (4353-95) ratio (lower ratio but much more impact).

Could you please file a bug with some representative example (same number of blocks, similar Scilab function) for further investigation ?

Note: having "costly" sciblk2 and sciblk4 also highly depends on your schema, for example having them on a continuous loop will make the solver call them on each timestep.

Regards,

--
Clément

From: Perrichon <perrichon.pierre at wanadoo.fr>
Sent: Monday, March 2, 2020 11:09 AM
To: 'Users mailing list for Scilab' <users at lists.scilab.org>; Clément David <Clement.David at esi-group.com>
Subject: RE: [Scilab-users] Xcos 6.1.0 - benchmark time test

Hello Clément,

Yes, I have some function blocks and expression blocks.
Must I understand that I have to write CBLOCK for scilab function or scilab expression or both ?

Here are other results for a more complex project name PELT1

Time request : 100 s

Results :
Xcos Scilab 5.5.2 :
Durée de la simulation : 258.3 s

Xcos Sciab 6.1.0 :
Durée de la simulation : 4353.4 s

So the ratio is 16.8 for PELT1

Other information :

Scilab 5.5.2 : time between click go and first scope on the screen = 5 s

Scilab 6.1.0 : time between click go and first scope on the screen = 95 s

Ratio=19

...and I also have other projects more complex

Pelt1 is for 1 needle (2 positonning loop)
Perlt6 for 6 !!! (7 positonning loop)


BR


De : users <users-bounces at lists.scilab.org<mailto:users-bounces at lists.scilab.org>> De la part de Clément David
Envoyé : vendredi 28 février 2020 10:10
À : Users mailing list for Scilab <users at lists.scilab.org<mailto:users at lists.scilab.org>>
Objet : Re: [Scilab-users] Xcos 6.1.0 - benchmark time test

Hello Pierre,

Are you using a block with its simulation function implemented in Scilab? Any C/C++ implemented block might perform the same at simulation time.

In 6.0.2, implementing Xcos blocks using the Scilab language had some performance issues. In 6.1.0, I tried to speed up things a little bit by reusing some allocated data structure during simulation time [1] ; more work might still be needed here.

[1]: http://cgit.scilab.org/scilab/commit/?id=bfe4f25275dc0d889817d10b63e10c9a0641ef32

Regards,

--
Clément

From: users <users-bounces at lists.scilab.org<mailto:users-bounces at lists.scilab.org>> On Behalf Of Perrichon
Sent: Friday, February 28, 2020 8:51 AM
To: 'Users mailing list for Scilab' <users at lists.scilab.org<mailto:users at lists.scilab.org>>
Subject: [Scilab-users] Xcos 6.1.0 - benchmark time test

Hello,

Here I test a PELTON basic algorithm under xcos, and record with tic-toc the simulation real time.
These programs have been set for 120 s (scope)

Results :
Xcos Scilab 5.5.2 :
Durée de la simulation : 45.4 s

Xcos Sciab 6.1.0 :
Durée de la simulation : 65.2 s

So the ratio is 1.44 for a basic sheme

Any explaination ?
Can that be improved ?

BR



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.scilab.org/pipermail/users/attachments/20200302/6d577d1b/attachment.htm>