I have a dual boot Dell XPS 15 i7 6th generation, running both Ubuntu Linux 17.10 and Windows 10. To my surprise and dismay, identical Stan code (I have tried many programs) runs much faster under Windows (up to factor 10). Is anyone familiar with this or have some advice? Thanks!
Make sure you have your ~/.R/Makevars file set correctly.
Thanks for the advice.
CXXFLAGS=-03 -mtune=native -march=native
CXXFLAGS= -Wno-unused_variable -Wno-unused-function -Wno-macro-redefined
CXXFLAGS+=-flto -Wno-unused-local-typedefs
CXXFLAGS += -Wno-ignored-attributes -Wno-deprecated-declarations
That’s what my Makevars contains
At this point CXXFLAGS
is set to -Wno-unused_variable -Wno-unused-function -Wno-macro-redefined
without the critical -03 -mtune=native -march=native
. Then, you +=
some less relevant stuff to that.
Or, to put it another way, it looks like the second line of Makevars has only a “=
” when it should have a “+=
”.
Thanks, that did the trick! Just changing “=” to “+=” in the second line, and the runtime just went from 750 sec to 42 sec. Kaboom!