I have rstudio server on an ec2 instance. It is not difficult to temporarily upgrade the number of vCPUs to 32 or higher. As I understand it, each chain can run on its own core. So, if you have more cores than chains then you are not benefiting much from the extra cores. Is this true?

Does having more cores than chains improve speed?

jonah May 17, 2018, 9:52pm 2

Yeah that’s right. Theres no benefit currently to having cores > chains. Until MPI makes it into the interfaces. Then it’s a totally new ballgame.

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