ghci uses an enormous amount of memory (recent 6.10 snapshots)
I've been trying out ghc 6.10 snapshots and I just discovered that ghci isn't usable for me. I'm running Gentoo on amd64 and I've both compiled 6.10 myself (using a variant of the ebuild from the Gentoo haskell overlay) and downloaded binary snapshots from haskell.org/ghc/dist/stable/dist (playing games with libedit.so to get them to work).
In both cases, ghci starts sucking up enormous amounts of memory on startup (quickly getting to 1.5G before my machine starts swapping - without loading any packages other than ghc-prim, integer and base). I've specifically observed this problem with 126.96.36.19981007 (i.e. RC1, if I'm reading things correctly), 188.8.131.5281019 and 184.108.40.20681020.
I don't know what's going on, but I didn't have this problem with ghc 6.8.3.