Hi, I have sent the pull request with the optionlist for Stampede - KNL on Bitbucket simfactory repo. I have tested this with a couple of thornlists including the einsteintoolkit.th and GW150914.th. This is still in experimental stage and so would be great if someone could also test it.
Working on benchmarking the performance on Stampede KNL, I was able to do some test runs using the GW150914 simulation. However, I have been running into some issues with it.
1. I tried running QC0 simulation on both Stampede SandyBridge and KNL. While it runs fine on Stampede but it crashes on KNL with this error -
while executing schedule bin BoundaryConditions, routine RotatingSymmetry180::Rot180_ApplyBC in thorn RotatingSymmetry180, file /work/04082/tg833814/Cactus_ETK_dev/arrangements/CactusNumerical/RotatingSymmetry180/src/rotatingsymmetry180.c:460: -> TAT/Slab can only be used if there is a single local component per MPI process TACC: MPI job exited with code: 134 I looked up at previous tickets and found the solution to increase the number of cores. But if the same simulation can be run on stampede on 64 cores, why does it require higher number of cores on KNL? Or is it some other issue?
2. I was able to run GW150914 on development queue (68 cores) and the speeds on Stampede were around 12.9M while that on KNL goes around 2.4M. To understand the reason for such small speeds, I tried running this on higher number of cores on Stampede (128) and it runs at speed of around 20.9M (tested the run for 12 hours). However, on doing the same in normal queue in KNL, the simulation crashes after a couple of iterations on KNL with some segmentation fault error. Also, before crashing, the speed on KNL is around 4.2M. I have attached the error file of the simulation.
Could someone please look at this? Let me know if you need any other information.
Thanks
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Bhavesh Khamesra
Graduate Student
Centre of Relativistic Astrophysics
Georgia Institute of Technology