I am excited to start using Julia 1.10.0 since I have a particular set of simulations which are allocation heavy (many small allocations) and I believe the GC is the current bottleneck. I want to make sure I am doing this right. I think to start, it would make sense to split total threads available…

Try this: --gcthreads=6,1 For me it gives a significant improvement. And I don’t think BLAS threads compete with GC threads because the GC stops everything else while running, but I might be wrong.

[image] TI36XPro: Also - I can double check the number of BLAS threads by doing BLAS.get_num_threads(). Is there any similar function for checking number of GC threads? Threads.ngcthreads() (although not public API) [image] TI36XPro: export OMP_NUM_THREADS=$COMPUTE_THREADS Note that, …

Thanks! I was using OMP_NUM_THREADS because on my cluster we have intel and AMD CPUs and I have the run script built so that if the architecture is AMD it won’t use MKL (defaults to OpenBLAS). Since I could possibly use either OpenBLAS or MKL depending on how slurm dispatches the run, I thought I s…

Good to know, I will try that today. Regarding whether the threads compete, that would also be good to know.

I cannot answer this question, but you should know that MKL also works nicely on AMD CPUs… Just benchmark yourself if OpenBLAS or MKL is better for your use case… Running MTK simulations multi-threaded, that only works with MKL…

Hm - yes I suppose I will have to then. I thought I had read somewhere that Intel made it run worse if it detected an AMD CPU.

Question About New GC Threads

General Usage

ufechner7 December 28, 2023, 5:47pm 8

This is the relevant link, might be outdated: How to circumvent Intel's AMD discrimination in MKL from v1.7 onwards?

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Question About New GC Threads

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