13 Mar
2013
13 Mar
'13
4:17 p.m.
Excerpts from Remi Turk's message of Wed Mar 13 13:09:18 -0700 2013:
Thanks for your quick reply. Could you elaborate on what "a bit of overhead" means? As a bit of context, I'm working on a small library for working with (im)mutable extendable tuples/records based on Storable and ForeignPtr, and I'm using StablePtr's as back-references to Haskell-land. Would you expect StablePtr's to have serious performance implications in such a scenario compared to, say, an IORef?
Yes, they will. Every stable pointer that is active has to be stuffed into a giant array, and the entire array must be traversed during every GC. See also: http://hackage.haskell.org/trac/ghc/ticket/7670 Edward