Not much memory overhead. If you look at your tree you will find that most nodes are only visited one or two times. There is a lot of noise in the fringes of the tree, so there are few duplicates. This also means that not sharing most of the tree has no impact on strength.
David > -----Original Message----- > From: [email protected] [mailto:computer-go- > [email protected]] On Behalf Of Michael Williams > Sent: Friday, August 10, 2012 9:42 AM > To: [email protected] > Subject: Re: [Computer-go] Kas Cup - results and prizes > > I imagine you can get around the lack of implicit information sharing > that you get with a shared tree by explicitly sharing information near > the root. > > But doesn't having separate trees mean a large memory overhead due to > duplicate nodes? > > > On Fri, Aug 10, 2012 at 9:26 AM, David Fotland <[email protected]> > wrote: > > Because my current approach seems to work just as well (or maybe > > better), and I haven't had time to code up a shared try and tune it up > > to validate that assumption. Chaslot's paper indicates perhaps that > > not having a shared tree is stronger. My guess is that they are about > > the same, so it's not worth the effort to change. > > > > david > > > >> -----Original Message----- > >> From: [email protected] [mailto:computer-go- > >> [email protected]] On Behalf Of Michael Williams > >> Sent: Friday, August 10, 2012 12:06 AM > >> To: [email protected] > >> Subject: Re: [Computer-go] Kas Cup - results and prizes > >> > >> Why don't you use a shared tree? > >> > >> > >> On Thu, Aug 9, 2012 at 11:49 PM, David Fotland > >> <[email protected]> > >> wrote: > >> > On an i7-2600 Many Faces does 11.4K pps with 4 threads, and 18.7k > >> > with > >> > 8 threads, a 64% increase, so the 2600 scales a little better than > >> > the 3770, but the 3770 is still a litte bit faster. > >> > > >> > > >> > > >> > david > >> > > >> > > >> > > >> > From: [email protected] > >> > [mailto:[email protected]] On Behalf Of Erik van der > >> > Werf > >> > Sent: Thursday, August 09, 2012 4:41 AM > >> > > >> > > >> > To: [email protected] > >> > Subject: Re: [Computer-go] Kas Cup - results and prizes > >> > > >> > > >> > > >> > I don't have an i7-2600, but I could run oakfoam on the 3930. I > >> > just downloaded it and it does compile. If you give me a list of > >> > gtp commands to run the benchmark, then I will send you the output > back. > >> > > >> > > >> > > >> > Erik > >> > > >> > > >> > > >> > On Thu, Aug 9, 2012 at 12:38 PM, ds <[email protected]> wrote: > >> > > >> > This is very interesting, > >> > > >> > I have not more than 10% with oakfoam on i7-2600K. Would be > >> > interesting if it is the processor or if you e.g. access more often > >> > memory instead of cache due to your code... > >> > > >> > Do you have the chance to run your program on a i7-2600? or do you > >> > have to much time and try > >> > https://bitbucket.org/francoisvn/oakfoam/wiki/Home > >> > on your i7-3930. If so, I would be very much interested in the > >> > number you get in the beginning of a 19x19 game without book:) > >> > > >> > > >> > Detlef > >> > > >> > Am Donnerstag, den 09.08.2012, 12:16 +0200 schrieb Erik van der > Werf: > >> > > >> >> On Thu, Aug 9, 2012 at 11:14 AM, Petr Baudis <[email protected]> wrote: > >> >> On Wed, Aug 08, 2012 at 09:08:47PM +0200, ds wrote: > >> >> > Hyperthreading does the trick, I have the experience it > >> >> increases the > >> >> > performance by about 10%. I think this is due to waiting > >> for > >> >> RAM I/O or > >> >> > things like that.... > >> >> > >> >> > >> >> Yes. With hyperthreading, performance per thread goes down > >> >> significantly, but total performance goes up by about 15%. > In > >> >> the > >> >> Pentium 4 era, hyperthreading did not usually pay off, but > >> >> with i7, > >> >> its performance is much better. The basic idea is that > there > >> >> are two > >> >> instruction pipelines that share the same ALU and other > >> >> processor units; > >> >> if one of the pipelines stalls (usually due to memory > fetch), > >> >> the other > >> >> can use the ALU in the meantime, or the two threads may > use > >> >> different > >> >> parts of the CPU altogether based on what the instructions > >> do. > >> >> > >> >> > >> >> > >> >> 10-15%, really, that low? For my program (on an i7-3930K, going > >> >> from > >> >> 6 to 12 threads) it is more in the order of 40% extra simulations > >> >> per second. > >> >> > >> >> > >> >> Erik > >> >> > >> >> > >> > > >> >> _______________________________________________ > >> >> Computer-go mailing list > >> >> [email protected] > >> >> http://dvandva.org/cgi-bin/mailman/listinfo/computer-go > >> > > >> > > >> > _______________________________________________ > >> > Computer-go mailing list > >> > [email protected] > >> > http://dvandva.org/cgi-bin/mailman/listinfo/computer-go > >> > > >> > > >> > > >> > > >> > _______________________________________________ > >> > Computer-go mailing list > >> > [email protected] > >> > http://dvandva.org/cgi-bin/mailman/listinfo/computer-go > >> _______________________________________________ > >> Computer-go mailing list > >> [email protected] > >> http://dvandva.org/cgi-bin/mailman/listinfo/computer-go > > > > _______________________________________________ > > Computer-go mailing list > > [email protected] > > http://dvandva.org/cgi-bin/mailman/listinfo/computer-go > _______________________________________________ > Computer-go mailing list > [email protected] > http://dvandva.org/cgi-bin/mailman/listinfo/computer-go _______________________________________________ Computer-go mailing list [email protected] http://dvandva.org/cgi-bin/mailman/listinfo/computer-go
