yade-users team mailing list archive

[Klaus Thoeni <klaus.thoeni@xxxxxxxxx>]

Hi Bruno,

i just tried your new implementation of the optimized contact detection in the 
trunk version. Have a look at the results:

script: examples/WireMatPM/wirecontacttest.py
200000 iterations, 1253 bodies
rev 2999: -j1 2min30sec, -j2 1min41sec, -j3 2min15sec
rev3001:-j1 2min37sec, -j2 1min53sec, -j3 2min15sec

other script:
22785 bodies
rev 2999: -j1 1min42sec, -j2 1min20sec, -j3 1min29sec
rev3001:-j1 2min38sec, -j2 2min17sec, -j3 2min44sec

This looks not good to me. I must say I didn't play with the parameters but I 
remember when I was testing with your collide2 branch (rev2925) I got much 
better performance. 

Any comments?

Klaus

On Tue, 24 Jan 2012 02:39:38 AM Bruno Chareyre wrote:
> Hi all,
> 
> The branch with optimized contact detection has been merged with trunk
> in bzr3000.
> According to my last tests and roughly speaking, yade is _3 times
> faster_ after this commit, but the result will be worst or better
> depending on the number of particles, the number of threads, the
> constitutive law used, the velocity of bodies, and a few other things.
> 
> If you don't compile yade, you can try the new version by installing or
> updating the yade-daily package.
> A few timings are reported on the wiki at
> https://www.yade-dem.org/wiki/Colliders_performace
> I would be glad to get feedback on the actual speedup in other simulations.
> I can imagine possible slowdown in extreme cases, although it is
> unlikely to happen (if it happens, then tuning the collider's parameters
> should fix the problem).
> If you feel like experimenting, you can play with the three parameters
> of the new collider: verletDist, targetInterv, and minSweepDistFactor.
> Reports can be very usefull as they will help to decide what is best
> best default combination for these parameters.
> 
> I hope we can release a stable version on this basis soon, when it is
> confirmed that the new collider is bug-free.
> 
> Best regards.
> 
> Bruno