How to speed up compilation time in linux

Question

While compiling under linux I use flag -j16 as i have 16 cores. I am just wondering if it makes any sense to use sth like -j32. Actually this is a quesiton about scheduling

Answer 1

The rule of thumb is to use the number of processors+1. Hyper-Thready counts, so a quad core CPU with HT should have -j9

Setting the value too high is counter-productive, if you do want to speed up compile times consider ccache to cache compiled objects that do not change in each compilation, and distcc to distribute the compilation across several machines.