On 12/04/2017 01:02 PM, Heiko Carstens wrote: > On Fri, Dec 01, 2017 at 12:58:47PM -0800, Randy Dunlap wrote: >> Hi, >> >> I used "maxcpus=1" on a recent x86 boot (4.15-rc1) and got 4 CPUs (all of >> them AFAICT). When I use "nr_cpus=1", I do get a hard limit of one CPU. >> >> >> A few boot log excerpts: >> >> [ 0.000000] smpboot: Allowing 8 CPUs, 4 hotplug CPUs >> ... >> [ 0.030007] smp: Bringing up secondary CPUs ... >> [ 0.030109] smp: Brought up 1 node, 1 CPU >> [ 0.030181] smpboot: Max logical packages: 4 >> [ 0.030255] smpboot: Total of 1 processors activated (4789.06 BogoMIPS) >> >> >> Is systemd (or something else) later onlining the other CPUs? >> >> /sys/devices/system/cpu/online is 0-3 >> /sys/devices/system/cpu/offline is 4-7 > > Check /lib/udev/rules.d/ for a rule that auto-onlines CPUs. > This behavior is distribution specific.
You got it in one try. Thanks. It would have taken me awhile to find that. I owe you a beer if you get to Portland, Oregon. :) -- ~Randy
