Rstan - (prob crazy question) is the compilation method changing via internet?

I would like to exclude a unlikely scenario.

One of my model slowed down of 4x in a week and I cannot find a clear reason.

Is it possible that the compiler is not static for my Rstan version (2.21.2) but is modified via connecting with web? (I see some pings as messages).

If so how can I avoid rstan contact with the web?

As of RStan 2.21, when you compile a model RStan downloads the latest version of the Stanc3 parser (that translates Stan syntax to c++ to be compiled). You can opt out of this by running: rstan_options(javascript = FALSE) when you first load the package.

However, a 4x slowdown is pretty dramatic so we’d really like to dig into this and figure out what caused the regression. Are you able to share the model, some data, and a rough estimate of the last time the model ran at the expected speed?


Also, if you can’t share the data, even just the model and the last time the model ran at the normal speed should be sufficient

That only checks whether your Stan program still parses with the next version of RStan. The C++ code that gets compiled is still generated by the old C++ parser.

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