if cache is your limiting factor that is usually shared. Also, if you are using processors with hyperthreading, it is possible. Or if bus bandwidth is your limiting factor... but if it is exactly 2x slower that is indeed very odd. My money is on the fact that you have a bottleneck somewhere else and those processors were operating below capacity the whole time and that now that you added more, it is becoming more obvious. If for instance, you had the following situation:
thread A creates a queue of tasks for the rest of the threads to do. If thread A isn't able to keep the queue full, then obviously more processors won't help. The only other though I have is that your compiler isn't writing code that allows for proper multithreading. Can you be more specific on which processors are giving you a hard time? - Nick On 2/22/07, Łukasz Lew <[EMAIL PROTECTED]> wrote:
I do not understand it. Maybe someone does? I've made some tests on 2 core processors, and I have strange results. Some of 2 core processors got results exactly 2x times worse than they should. Why? I have no idea. But 2.8 Ghz 2 core works exactly like my 1.4 laptop. Also version of g++ does matter. Łukasz On 2/21/07, Brian Slesinsky <[EMAIL PROTECTED]> wrote: > The only real change is to link against the Boost libraries I > installed using DarwinPorts. Here are the diffs: > > -CFLAGS += -Wall #-static #-Wno-long-long -Wextra -Wno-variadic-macros > +CFLAGS += -Wall -I/opt/local/include -L/opt/local/lib > > It's a desktop and I don't see any options for power management. > Maybe it's just a difference in processors? It's a two core chip but > perhaps not as fast at single-threaded apps. Adding multithreading > might help. > > - Brian > > On 2/21/07, Łukasz Lew <[EMAIL PROTECTED]> wrote: > > On 2/21/07, Brian Slesinsky <[EMAIL PROTECTED]> wrote: > > > [resending; apologies if you get this twice.] > > > > > > Hi, > > > > Hi Brian, > > > > > > > > This is my first post to the list, so I'll introduce myself: I'm a > > > software developer and just getting started with playing Go. I read > > > the article in the Economist and thought that the work on Monte-Carlo > > > based Go programs sounds promising. I'm not interested in writing my > > > own Go program but would like to experiment with improving existing > > > programs. > > > > Have fun ;) > > > > > > > > I built and started libego on an iMac with a 2GHz Intel Core Duo. The > > > initial benchmark reports these results: > > > > > > Performance: > > > 100000 playouts > > > 1.84255 seconds > > > 54.2727 kpps > > > Black wins = 43983 > > > White wins = 56017 > > > P(black win) = 0.43983 > > > > > > Are these numbers to be expected? > > > > They are correct, except rather low performance. > > It should be rather about 80 kpps (kilo playouts per second) > > > > There are few possible reasons for this: > > - You are using a laptop with power management > > - You changed Makefile or some source files to make it compile on Mac? > > > > Best Regards, > > Łukasz Lew > > > > > > > > - Brian > > > _______________________________________________ > > > computer-go mailing list > > > computer-go@computer-go.org > > > http://www.computer-go.org/mailman/listinfo/computer-go/ > > > > > > > _______________________________________________ > > computer-go mailing list > > computer-go@computer-go.org > > http://www.computer-go.org/mailman/listinfo/computer-go/ > > > > _______________________________________________ > computer-go mailing list > computer-go@computer-go.org > http://www.computer-go.org/mailman/listinfo/computer-go/ > _______________________________________________ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
_______________________________________________ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
