'import ccall unsafe' and parallelism

Carter Schonwald carter.schonwald at gmail.com
Thu Aug 14 21:10:22 UTC 2014

have a smart wrapper around you ffi call, and if when you think the ffi
call will take more than 1 microsecond, ALWAYS use the safe ffi call,
i do something like this in an FFI i wrote, it works great

On Thu, Aug 14, 2014 at 1:20 PM, Christian Höner zu Siederdissen <
choener at tbi.univie.ac.at> wrote:

> Thanks,
> I've played around some more and finally more than one capability is
> active. And indeed, unsafe calls don't block everything. I /had/
> actually read that but when I saw the system spending basically only
> 100% cpu time, I'd thought to ask.
> One problem with this program seems to be that the different tasks are
> of vastly different sizes. Inputs range from ~ 7x10^1 to ~ 3x10^7
> elements inducing waits with the larger problem sizes.
> We'll keep the program single-threaded for now as this also keeps memory
> consumption at only 25 gbyte instead of the more impressive 70 gbyte in
> multi-threaded mode ;-)
> Viele Gruesse,
> Christian
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