Momentarily, the Haskell IDE Engine (HIE) is in a bad shape. In its version 0.2.2, it eats a huge amount of memory, much more than my machine can provide (I have 8 GB in total). Users have already reported this, and even though there is a memory leak in GHC, Haskell IDE Engine developers haven’t started tackling this problem yet. What you can do in the meantime is to provide runtime system (RTS) options to an engine executable to limit its heap and stack memory sizes. For example, you can write a wrapper script around the
hie executable that would run it with the following RTS options:
hie +RTS -c -M1500M -K1G -A16M -RTS --lsp $@
This limits the heap size to 1500 MB and the stack size to 1 GB. The executable will crash once it surpasses these limits, but your editor (e.g., Atom) should restart it. In other words, HIE will keep on crashing and restarting in a loop, which is ugly, but that’s what we have now.