On Sun, Sep 14, 2008 at 08:38:00PM -0500, Stephen Montgomery-Smith wrote: > I have a dual core amd64 on which I run a processor intensive numerical > program. I had been frustrated because it seemed to run 3 or 4 times > faster under Linux. But with a recent upgrade of FreeBSD-CURRENT, it > now goes at about the same speed as Linux. > > The program takes about an hour. For the first minute, the program runs > rather slowly, but then it is as if the operating system finds its way, > and suddenly it speeds up. "top -H" suggests that for the first minute > that one thread is going really slowly, and is perhaps being starved or > something. > > My question is - why is this happening, and is this something I should > expect? Are there certain switches or sysctls I can set to make it go > fast from the get go? It looks like you're running powerd (see in /etc/rc.conf). It can take up to a minute for the load average of the machine to exceed a certain threshold where powerd would finally bump the cpu(s) to full speed. As for sysctls, check the speed with something like: # sysctl dev.cpu.0 > Thanks, Stephen Regards, -cpghost. -- Cordula's Web. http://www.cordula.ws/Received on Mon Sep 15 2008 - 16:54:44 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:39:35 UTC