heap and code in ghci

Simon Marlow simonmar@microsoft.com
Fri, 27 Apr 2001 11:32:40 +0100

> Let, for example, all the  .o  modules were prepared, and we=20
> command
>          ghci ... +RTS -Mxxm -RTS
>          ...
>            Loading package std ... linking ... done.
>          Prelude> :l BPrelude
>          ...
> and then try to find  sum [1..n].
> In my experiment
>   xx =3D  7                   does not allow to load the program,
>         8,  sum [1..66000]  yields  "Heap exhausted",
>        10,  sum [1..77000]  yields  2964538500.=20
> Probably, this  xx Mb  is for  binary program + heap.
> ghci  loads .o modules, they take some part of  xx,
> and all the rest is for the heap.
> Right?

Nope.  The -M flag affects the size of the heap only; object files are
loaded outside the heap.  If you're running out of heap with a maximum
size of 8M, it's probably because the heap is full of interfaces (i.e.
the in-memory copy of the .hi file).