Hello, I noticed a weird behavior in julia 1.5.1 performance (e. g. loading packages) compared to julia 1.1.0. I have a batch script which starts various julia scripts simultaneously on a cluster. In a simplified version it looks like ... #SBATCH --ntasks 16 ... for ((i=1; i<=16; i++)) do sr…

Someone remind me please - there is a Julia package which deals with race conditions when packages are being compiled. this was referenced recently.

While someone can answer your question, do you suggest that I recompile everything on 1.5.1? Could that help?

Unfortunately it does affect every code, not only the using SomePackege, changing the script to using Dates println(now()) @time A = rand(10_000_000) gives the very same increase in time approximately proportional to the number of tasks. number of tasks time in s 40 1.663574 20 0.72895…

I think you are refering to this: [image] ANN: Parallel `for` loops in FLoops.jl with composable and extensible fold-based API Package Announcements A while ago I posted FLoops.jl RFC that demonstrates alternative for loop framework on top of Transducers.jl . FLoops.jl le…

I have found the part which is responsible for the slowdown. It is the memory allocation (I accidentally did not included it in the batch script in this post, it is now edited). When I do not set the memory, the times are fine… Edit: sorry, this does not solve the issue because if I do not provide …

Related to @johnh ’s comment, the issue may be due to a recent change that makes the generation of the precompilation caches atomic, to avoid race conditions. If that’s the issue, you can take a look at the docs for possible workarounds. The easiest thing to try is to start Julia with --compiled-mod…

Hello, thanks for the explanation. I was able to finally solve it by using srun -n 1 --exclusive /path/to/julia_version-number/bin/julia -O3 -- script.jl $i > $i.log & and including #SBATCH --mem-per-cpu=500 in the batch script. Could you imagine that this memory/CPU management somehow influence…

Julia 1.5.1 slows down when running multiple instances in parallel

General Usage Performance

oheil September 2, 2020, 9:41am 5

I think you are refering to this:

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Julia 1.5.1 slows down when running multiple instances in parallel

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