3 Mar
2009
3 Mar
'09
5:41 p.m.
allbery:
On 2009 Mar 3, at 12:31, mwinter@brocku.ca wrote:
In both runs the same computations are done (sequentially resp. parallel), so the gc should be the same. But still using 2 cores is much slower than using 1 core (same program - no communication).
The same GCs are done, but GC has to be done on a single core (currently; parallel GC is in development) so you will see a lot more lock contention when the GC kicks in.
Assuming he is using GHC 6.10, the parallel GC is enabled by default when you use -Nn where n > 1. That's is -N4 will use -g4 (4 cores to collect). So GC should be the same or a little faster. -- Don