Building on limited memory environments (or does -M really work?)

Niklas Hamb├╝chen mail at
Wed Nov 8 19:21:14 UTC 2017

Hey Saurabh,

from my experience with CircleCI it builds on machines with e.g. 32
cores showing up in htop (but allows you to use way less that that).

But ghc sees 32 cores so -j will compile up to 32 modules at the same
time (thus using tons of RAM).

I solved that by setting -jN to the actual number of cores I bought from


On 21/10/17 14:36, Saurabh Nanda wrote:
> We're struggling to get our build pipeline working on CircleCI, which
> has a 4GB RAM limit.

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