Yambo Community Forum

Dear sir,
I am doing tdbse Shg on a system but my collision calc always get stuck at 62% or at 97%, I'm attaching coll input, log and report, please suggest a way so that my calculation can run smoothly, I am stuck in this step for days, i dont feel memory is an issue and it'll run successfully on single core but takes time to complete. Looking fwd to your valuable response.
regards
Sohan

Also I have configured and compiled 5.3.0 using

./configure --enable-dp --enable-mpi FC=ifort CC=icc

I hope this is not causing the mishap.
I have attached config log.
regards
sohan

Dear Sohan

please try to compile yambo_rt without double-precision and use it to calculate collisions,
it is much faster and collisions in single precision are perfect for real-time dynamics.

However do not forget that for the dynamics you need yambo_nl

best
Claudio

Dear Sir,
Thank you for the kind response, I'll have two different yambo with single and double precision and will give a try with single precision. Will report you the outcomes.
regards
Sohan

Dear sir,
The stuck issue is still there even after configuring with single precision. I have attached again report, input, log and config log. Please suggest any solution.
regards
sohan

Dear sohan

try to setup different parallelization scheme and see if it works, just do:
yambo_rt -X s -collisions -potential h+sex -V par

then you can try to parallelize:

RT_CPU= "1,4,1,4" # [PARALLEL] CPUs for each role
RT_ROLEs= "k,b,q,qp" # [PARALLEL] CPUs roles (k,b,q,qp)

or

RT_CPU= "1,1,1,16" # [PARALLEL] CPUs for each role
RT_ROLEs= "k,b,q,qp" # [PARALLEL] CPUs roles (k,b,q,qp)

and check if it works.
Then remember that your parameters are not converged you should increase at least
HARRLvcs= 3000 mHa # [HA] Hartree RL components
EXXRLvcs= 3000 mHa # [XX] Exchange RL components
CORRLvcs= 3000 mHa # [GW] Correlation RL components

and more bands in X.
best
Claudio

Dear sir,
There's one thing I noticed while running collisions calculation in parallel, that it will stuck for particular no. of processors and will run for one certain number of processors. In my case I was able to run collision calculation

mpirun -np N yambo_rt

when N= 1,2,3,5,11,19 and was getting stuck when N= 4,8,7,16,12
What could be the reason behind it?
regards
sohan

It is an issue which was also noticed in the past and never solved so far.

At present we do not have a solution. We are checking the code in order to fix it.

Best,
D.