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Problems with multi-core in R4.x

Report bugs or highlight issues with Apollo functions. At a minimum, please include the part of the output where you believe the bug is manifested. Ideally, please share your model file.
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yschung
Posts: 3
Joined: 13 Jul 2020, 05:16

Problems with multi-core in R4.x

Post by yschung »

Here is feedback to those who use Mac OS to run R4.X via RStudio. Currently, RStudio does not support parallel::makeCluster(), meaning that you may not be able to run multi-cores using nCores in apollo_control. But nCores is fine if you run R4.X and apollo via terminal. The issue may be fixed in the next version of RStudio.

Here is the link to the discussion of parallel::makeCluster() problems in RStudio with R4.X. [https://github.com/rstudio/rstudio/issues/6692]

Cheers,
Yishih
stephanehess
Site Admin
Posts: 974
Joined: 24 Apr 2020, 16:29

Re: Problems with multi-core in R4.x

Post by stephanehess »

Hi Yishih

Thanks for bringing this issue to our attention. This is indeed a wider RStudio issue rather than an Apollo issue. We have implemented a fix in v0.1.1 that creates the cores sequentially on MacOS systems. It adds a small additional setup time in creating the cores but has no impact on run times after that.

Stephane
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Stephane Hess
www.stephanehess.me.uk
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