Sorry, that's not right of course. The 64K version spends on average the same time, but plays 100 ELO stronger. Otherwise there would be no point :)
Mark On Aug 12, 2012, at 6:07 PM, Mark Boon <[email protected]> wrote: > Interesting, I'd have thought it would matter quite bit, especially with > higher numbers of threads. > > One thing I found (quite a few years back now already) is that you can > optimize a lot by doing the following: when one node has so many more wins > than the second best that it can't be overtaken even if the second best wins > all of the remaining playouts, abort thinking. With a couple of extensions to > this general idea (aborting not just when it's impossible, just very unlikely > to be overtaken) I found that a player that does 64K lightweight simulations > using this method spends the same time and plays the same level as one that > does a fixed 32K simulations. Roughly. The higher the number of simulations, > the bigger the savings. > > This type of optimization must be much harder with root-level > parallelization, so you'd have to factor that in when comparing methods. > > Mark > > On Aug 10, 2012, at 9:55 PM, "David Fotland" <[email protected]> wrote: > >> 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 _______________________________________________ Computer-go mailing list [email protected] http://dvandva.org/cgi-bin/mailman/listinfo/computer-go
