On Saturday, January 07, 2012 08:40:23 PM Kent A. Reed did opine: > On 1/5/2012 8:46 PM, gene heskett wrote: > > Where can I find some real docs on this isolcpu thingy? > > Gene: > > Quoting from kernel.org: > > isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler. > Format: > <cpu number>,...,<cpu number> > or > <cpu number>-<cpu number> > (must be a positive range in ascending order) > or a mixture > <cpu number>,...,<cpu number>-<cpu number> > > 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. > > It's straightforward to set this parameter in classic grub. I did a > piece on the Wiki a while ago about how to set this parameter in a grub2 > environment
I've read the first from kernel.org, and your wiki article (which I expect to do on the new box arriving late Monday, thanks), but both articles leave me scratching my head a wee bit. It seems to me that if one is going to take a cpu core out of the SMP scheduling effectively isolating it so its doing nothing, then one should have a matching command associated with the RTAI load that specifically puts the RTAI core to run on this 'saved' core, but I haven't found how this can be assured to happen. So that is my real & not very well asked question, Kent. Hows the missus doing? Better I hope. > > http://wiki.linuxcnc.org/emcinfo.pl/The_Isolcpus_Boot_Parameter_And_GRUB > 2 > > Regards, > Kent > > > ------------------------------------------------------------------------ > ------ Ridiculously easy VDI. With Citrix VDI-in-a-Box, you don't need a > complex infrastructure or vast IT resources to deliver seamless, secure > access to virtual desktops. With this all-in-one solution, easily > deploy virtual desktops for less than the cost of PCs and save 60% on > VDI infrastructure costs. Try it free! > http://p.sf.net/sfu/Citrix-VDIinabox > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> Beauty may be skin deep, but ugly goes clear to the bone. -- Redd Foxx ------------------------------------------------------------------------------ Ridiculously easy VDI. With Citrix VDI-in-a-Box, you don't need a complex infrastructure or vast IT resources to deliver seamless, secure access to virtual desktops. With this all-in-one solution, easily deploy virtual desktops for less than the cost of PCs and save 60% on VDI infrastructure costs. Try it free! http://p.sf.net/sfu/Citrix-VDIinabox _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
