On Tue, Aug 23, 2011 at 2:15 AM, Vaibhav Jain <vjoss197@xxxxxxxxx> wrote: > Hi, > Thanks for replying but I want to do this in a SMP machine. > Please help! > > Thanks > Vaibhav Jain > > On Wed, Aug 17, 2011 at 10:53 PM, Vladimir Murzin <murzin.v@xxxxxxxxx> > wrote: >> >> On Wed, Aug 17, 2011 at 11:01 PM, Vaibhav Jain <vjoss197@xxxxxxxxx> wrote: >> > Hi, >> > >> > I am looking into running a program on one of the cores which is >> > isolated >> > (logically offline ) >> > from the rest of the cores. I have come to that the command >> > echo 0 > /sys/device/system/cpu/<core num>/online >> > >> > will make a core logically offline, >> > What I need to do now is to run a program on this offline core. Please >> > suggest on how to proceed. >> > >> > Thanks! >> > Vaibhav Jain >> > _______________________________________________ >> > Kernelnewbies mailing list >> > Kernelnewbies@xxxxxxxxxxxxxxxxx >> > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >> > >> > >> Hi Vaibhav, >> >> I think it's impossible to run out a process on unplugged CPU. May be >> AMP[1] is what you need, but it's a bit different approach. >> >> [1]http://en.wikipedia.org/wiki/Asymmetric_multiprocessing > > Hi Vaibhav, There is one more approach, but it's not operate on off-lined CPU. Have a look at isolcpu kernel boot option. Description in Documentation/kernel-parameters.txt says: This option can be used to specify one or more CPUs to isolate from the general SMP balancing and scheduling algorithms. You can move a process onto or off an "isolated" CPU via the CPU affinity syscalls or cpuset. <cpu number> begins at 0 and the maximum value is "number of CPUs in system - 1". This option is the preferred way to isolate CPUs. The alternative -- manually setting the CPU mask of all tasks in the system -- can cause problems and suboptimal load balancer performance. _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
