Results 1 to 6 of 6

Thread: KVM shows wrong number of CPU's

  1. #1

    Default KVM shows wrong number of CPU's

    On my Fujitsu Primergy RX300S6 i got 2x Intel Xeon CPU X5650
    and the Out-Of-The-Box-Xen-Kernel shows me 24 CPU's.
    Also the virt-manager offers me 24 CPU's to use for my virtual machines.

    When i start the machine with the Standard-Dektop-Kernel the kernel
    only sees 12 CPU's.

    Below is the output of lscpu for both kernels.

    According to /boot/config-3.1.9-1.4-desktop and /boot/config-3.1.9-1.4-xen
    the number of CPU's is set to 512 (CONFIG_NR_CPUS=512).

    How can i teach my kernel to see the rest of the CPU's ?

    Any hint will be greatly appreciated.


    Thanks



    ----------------------------------------------
    Xen -- openSUSE 12.1 - 3.1.9-1.4

    server01:~ # lscpu
    Architecture: x86_64
    CPU op-mode(s): 32-bit, 64-bit
    Byte Order: Little Endian
    CPU(s): 24
    On-line CPU(s) list: 0-23
    Thread(s) per core: 1
    Core(s) per socket: 1
    Socket(s): 24
    Vendor ID: GenuineIntel
    CPU family: 6
    Model: 44
    Stepping: 2
    CPU MHz: 2666.832
    BogoMIPS: 5401.35
    Hypervisor vendor: Xen
    Virtualization type: none
    L1d cache: 32K
    L1i cache: 32K
    L2 cache: 256K
    L3 cache: 12288K

    ----------------------------------------------
    Desktop -- openSUSE 12.1 - 3.1.9-1.4

    server01:~ # lscpu
    Architecture: x86_64
    CPU op-mode(s): 32-bit, 64-bit
    Byte Order: Little Endian
    CPU(s): 12
    On-line CPU(s) list: 0-11
    Thread(s) per core: 1
    Core(s) per socket: 6
    Socket(s): 2
    NUMA node(s): 1
    Vendor ID: GenuineIntel
    CPU family: 6
    Model: 44
    Stepping: 2
    CPU MHz: 2666.988
    BogoMIPS: 5332.55
    Virtualization: VT-x
    L1d cache: 32K
    L1i cache: 32K
    L2 cache: 256K
    L3 cache: 12288K
    NUMA node0 CPU(s): 0-11

  2. #2
    Join Date
    Jun 2008
    Location
    Kansas City Area, Missouri, USA
    Posts
    7,235

    Default Re: KVM shows wrong number of CPU's

    On 06/27/2012 07:06 AM, senblue wrote:
    >
    > On my Fujitsu Primergy RX300S6 i got 2x Intel Xeon CPU X5650
    > and the Out-Of-The-Box-Xen-Kernel shows me 24 CPU's.
    > Also the virt-manager offers me 24 CPU's to use for my virtual
    > machines.
    >
    > When i start the machine with the Standard-Dektop-Kernel the kernel
    > only sees 12 CPU's.
    >
    > Below is the output of lscpu for both kernels.
    >
    > According to /boot/config-3.1.9-1.4-desktop and
    > /boot/config-3.1.9-1.4-xen
    > the number of CPU's is set to 512 (CONFIG_NR_CPUS=512).
    >
    > How can i teach my kernel to see the rest of the CPU's ?
    >
    > Any hint will be greatly appreciated.


    You should compare the two versions of dmesg for a clue regarding why the
    desktop only sees half of the CPUs. It may be a kernel bug.


  3. #3

    Default Re: KVM shows wrong number of CPU's

    Quote Originally Posted by lwfinger View Post
    On 06/27/2012 07:06 AM, senblue wrote:
    >

    > How can i teach my kernel to see the rest of the CPU's ?
    >
    > Any hint will be greatly appreciated.


    You should compare the two versions of dmesg for a clue regarding why the
    desktop only sees half of the CPUs. It may be a kernel bug.

    I dont want to spam this board with excessive listings
    therefore below only some of the output of dmesg concerning cpus.
    And only from the desktop-kernel.
    The kernel sees only one cpu (CPU0).
    There is no obvious error message, while booting
    the desktop-kernel.
    Or am i missing something ?

    As of my initial posting lscpu shows
    two sockets, six cores per socket an one thread
    per core , so 2x6x1 => 12 logical cpus

    I made an online update to kernel 3.1.10-1.9
    and tried the default-kernel and the vanilla-kernel.
    Always the same result.

    Booting an ubuntu-12.04-live-system with kernel 3.2.0-23-generic
    gives me the 24 cpus like the xen-kernel of opensuse 12.1.

    One can say, why not use the opensuse-xen-kernel ?
    I changed to kvm because of totally unpredictable and
    unexplainable system freezes with the xen-kernel.

    Possibly these freezes where caused by bugs in the acpi-code,
    because a second RX300 running stable for two month with acpi=off.

    But i invested lot of time in buildding the virtual machines under
    KVM. So i would prefer to stay with it.



    [ 0.000000] Initializing cgroup subsys cpuset
    [ 0.000000] Initializing cgroup subsys cpu
    [ 0.000000] Linux version 3.1.9-1.4-desktop (geeko@buildhost) (gcc version 4.6.2 (SUSE Linux) ) #1 SMP PREEMPT Fri Jan 27 08:55:10 UTC 2012 (efb5ff4)
    [ 0.000000] Command line: root=/dev/system/root resume=/dev/system/swap splash=silent quiet showopts acpi=off vga=0x31a
    [ 0.000000] BIOS-provided physical RAM map:
    [ 0.000000] BIOS-e820: 0000000000000000 - 000000000009c400 (usable)
    [ 0.000000] BIOS-e820: 000000000009c400 - 00000000000a0000 (reserved)
    [ 0.000000] BIOS-e820: 00000000000e4000 - 0000000000100000 (reserved)
    [ 0.000000] BIOS-e820: 0000000000100000 - 00000000bf7a0000 (usable)
    [ 0.000000] BIOS-e820: 00000000bf7a0000 - 00000000bf7b9000 (ACPI data)
    [ 0.000000] BIOS-e820: 00000000bf7b9000 - 00000000bf7ba000 (ACPI NVS)
    [ 0.000000] BIOS-e820: 00000000bf7ba000 - 00000000c0000000 (reserved)
    [ 0.000000] BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)
    [ 0.000000] BIOS-e820: 00000000fec00000 - 00000000fed00000 (reserved)
    [ 0.000000] BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
    [ 0.000000] BIOS-e820: 00000000ffa00000 - 0000000100000000 (reserved)
    [ 0.000000] BIOS-e820: 0000000100000000 - 0000002440000000 (usable)
    [ 0.000000] NX (Execute Disable) protection: active
    [ 0.000000] DMI present.
    [ 0.000000] DMI: FUJITSU PRIMERGY RX300 S6 /D2619, BIOS 6.00 Rev. 1.08.2619.N1 10/06/2010
    [ 0.000000] e820 update range: 0000000000000000 - 0000000000010000 (usable) ==> (reserved)
    [ 0.000000] e820 remove range: 00000000000a0000 - 0000000000100000 (usable)
    [ 0.000000] No AGP bridge found
    [ 0.000000] last_pfn = 0x2440000 max_arch_pfn = 0x400000000
    [ 0.000000] MTRR default type: uncachable
    [ 0.000000] MTRR fixed ranges enabled:
    [ 0.000000] 00000-9FFFF write-back
    [ 0.000000] A0000-BFFFF uncachable
    [ 0.000000] C0000-FFFFF write-protect
    [ 0.000000] MTRR variable ranges enabled:
    [ 0.000000] 0 base 00C0000000 mask FFC0000000 uncachable
    [ 0.000000] 1 base 0000000000 mask E000000000 write-back
    [ 0.000000] 2 base 2000000000 mask FC00000000 write-back
    [ 0.000000] 3 base 2400000000 mask FFC0000000 write-back
    [ 0.000000] 4 disabled
    [ 0.000000] 5 disabled
    [ 0.000000] 6 disabled
    [ 0.000000] 7 disabled
    [ 0.000000] 8 disabled
    [ 0.000000] 9 disabled
    [ 0.000000] x86 PAT enabled: cpu 0, old 0x7040600070406, new 0x7010600070106
    [ 0.000000] e820 update range: 00000000c0000000 - 0000000100000000 (usable) ==> (reserved)
    [ 0.000000] last_pfn = 0xbf7a0 max_arch_pfn = 0x400000000
    [ 0.000000] found SMP MP-table at [ffff8800000f7ef0] f7ef0
    [ 0.000000] initial memory mapped : 0 - 20000000
    [ 0.000000] Base memory trampoline at [ffff880000097000] 97000 size 20480
    [ 0.000000] Using GB pages for direct mapping
    [ 0.000000] init_memory_mapping: 0000000000000000-00000000bf7a0000
    [ 0.000000] 0000000000 - 0080000000 page 1G
    [ 0.000000] 0080000000 - 00bf600000 page 2M
    [ 0.000000] 00bf600000 - 00bf7a0000 page 4k
    [ 0.000000] kernel direct mapping tables up to bf7a0000 @ 1fffd000-20000000
    [ 0.000000] init_memory_mapping: 0000000100000000-0000002440000000
    [ 0.000000] 0100000000 - 2440000000 page 1G
    [ 0.000000] kernel direct mapping tables up to 2440000000 @ bf79f000-bf7a0000
    [ 0.000000] RAMDISK: 37b34000 - 37ff0000
    [ 0.000000] No NUMA configuration found
    [ 0.000000] Faking a node at 0000000000000000-0000002440000000
    [ 0.000000] Initmem setup node 0 0000000000000000-0000002440000000
    [ 0.000000] NODE_DATA [000000243ffec000 - 000000243fffffff]
    [ 0.000000] [ffffea0000000000-ffffea007edfffff] PMD -> [ffff8823af600000-ffff88242d5fffff] on node 0
    [ 0.000000] Zone PFN ranges:
    [ 0.000000] DMA 0x00000010 -> 0x00001000
    [ 0.000000] DMA32 0x00001000 -> 0x00100000
    [ 0.000000] Normal 0x00100000 -> 0x02440000
    [ 0.000000] Movable zone start PFN for each node
    [ 0.000000] early_node_map[3] active PFN ranges
    [ 0.000000] 0: 0x00000010 -> 0x0000009c
    [ 0.000000] 0: 0x00000100 -> 0x000bf7a0
    [ 0.000000] 0: 0x00100000 -> 0x02440000
    [ 0.000000] On node 0 totalpages: 37746476
    [ 0.000000] DMA zone: 56 pages used for memmap
    [ 0.000000] DMA zone: 5 pages reserved
    [ 0.000000] DMA zone: 3919 pages, LIFO batch:0
    [ 0.000000] DMA32 zone: 14280 pages used for memmap
    [ 0.000000] DMA32 zone: 765912 pages, LIFO batch:31
    [ 0.000000] Normal zone: 505344 pages used for memmap
    [ 0.000000] Normal zone: 36456960 pages, LIFO batch:31
    [ 0.000000] SFI: Simple Firmware Interface v0.81 http://simplefirmware.org
    [ 0.000000] Intel MultiProcessor Specification v1.4
    [ 0.000000] MPTABLE: OEM ID: FSCD2619
    [ 0.000000] MPTABLE: Product ID: PRIMERGY
    [ 0.000000] MPTABLE: APIC at: 0xFEE00000
    [ 0.000000] Processor #0 (Bootup-CPU)
    [ 0.000000] Processor #2
    [ 0.000000] Processor #4
    [ 0.000000] Processor #16
    [ 0.000000] Processor #18
    [ 0.000000] Processor #20
    [ 0.000000] Processor #32
    [ 0.000000] Processor #34
    [ 0.000000] Processor #36
    [ 0.000000] Processor #48
    [ 0.000000] Processor #50
    [ 0.000000] Processor #52
    [ 0.000000] IOAPIC[0]: apic_id 6, version 32, address 0xfec00000, GSI 0-23
    [ 0.000000] IOAPIC[1]: apic_id 7, version 32, address 0xfec80000, GSI 24-47
    [ 0.000000] Processors: 12
    [ 0.000000] SMP: Allowing 12 CPUs, 0 hotplug CPUs
    [ 0.000000] nr_irqs_gsi: 64
    [ 0.000000] PM: Registered nosave memory: 000000000009c000 - 000000000009d000
    [ 0.000000] PM: Registered nosave memory: 000000000009d000 - 00000000000a0000
    [ 0.000000] PM: Registered nosave memory: 00000000000a0000 - 00000000000e4000
    [ 0.000000] PM: Registered nosave memory: 00000000000e4000 - 0000000000100000
    [ 0.000000] PM: Registered nosave memory: 00000000bf7a0000 - 00000000bf7b9000
    [ 0.000000] PM: Registered nosave memory: 00000000bf7b9000 - 00000000bf7ba000
    [ 0.000000] PM: Registered nosave memory: 00000000bf7ba000 - 00000000c0000000
    [ 0.000000] PM: Registered nosave memory: 00000000c0000000 - 00000000e0000000
    [ 0.000000] PM: Registered nosave memory: 00000000e0000000 - 00000000f0000000
    [ 0.000000] PM: Registered nosave memory: 00000000f0000000 - 00000000fec00000
    [ 0.000000] PM: Registered nosave memory: 00000000fec00000 - 00000000fed00000
    [ 0.000000] PM: Registered nosave memory: 00000000fed00000 - 00000000fee00000
    [ 0.000000] PM: Registered nosave memory: 00000000fee00000 - 00000000fee01000
    [ 0.000000] PM: Registered nosave memory: 00000000fee01000 - 00000000ffa00000
    [ 0.000000] PM: Registered nosave memory: 00000000ffa00000 - 0000000100000000
    [ 0.000000] Allocating PCI resources starting at c0000000 (gap: c0000000:20000000)
    [ 0.000000] Booting paravirtualized kernel on bare hardware
    [ 0.000000] setup_percpu: NR_CPUS:512 nr_cpumask_bits:512 nr_cpu_ids:12 nr_node_ids:1
    [ 0.000000] PERCPU: Embedded 27 pages/cpu @ffff88243fc00000 s78208 r8192 d24192 u131072
    [ 0.000000] pcpu-alloc: s78208 r8192 d24192 u131072 alloc=1*2097152
    [ 0.000000] pcpu-alloc: [0] 00 01 02 03 04 05 06 07 08 09 10 11 -- -- -- --
    [ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 37226791
    [ 0.000000] Policy zone: Normal
    [ 0.000000] Kernel command line: root=/dev/system/root resume=/dev/system/swap splash=silent quiet showopts acpi=off vga=0x31a
    [ 0.000000] bootsplash: silent mode.
    [ 0.000000] PID hash table entries: 4096 (order: 3, 32768 bytes)
    [ 0.000000] Checking aperture...
    [ 0.000000] No AGP bridge found
    [ 0.000000] Memory: 148832796k/152043520k available (5797k kernel code, 1057616k absent, 2153108k reserved, 7771k data, 940k init)
    [ 0.000000] Preemptible hierarchical RCU implementation.
    [ 0.000000] NR_IRQS:33024 nr_irqs:1184 16
    [ 0.000000] Console: colour dummy device 80x25
    [ 0.000000] console [tty0] enabled
    [ 0.000000] allocated 1207959552 bytes of page_cgroup
    [ 0.000000] please try 'cgroup_disable=memory' option if you don't want memory cgroups
    [ 0.001000] Fast TSC calibration using PIT
    [ 0.002000] Detected 2666.988 MHz processor.
    [ 0.000004] Calibrating delay loop (skipped), value calculated using timer frequency.. 5333.97 BogoMIPS (lpj=2666988)
    [ 0.000007] pid_max: default: 32768 minimum: 301
    [ 0.000063] Security Framework initialized
    [ 0.000076] AppArmor: AppArmor initialized
    [ 0.018399] Dentry cache hash table entries: 33554432 (order: 16, 268435456 bytes)
    [ 0.090049] Inode-cache hash table entries: 16777216 (order: 15, 134217728 bytes)
    [ 0.120631] Mount-cache hash table entries: 256
    [ 0.120761] Initializing cgroup subsys cpuacct
    [ 0.120765] Initializing cgroup subsys memory
    [ 0.120785] Initializing cgroup subsys devices
    [ 0.120788] Initializing cgroup subsys freezer
    [ 0.120790] Initializing cgroup subsys net_cls
    [ 0.120791] Initializing cgroup subsys blkio
    [ 0.120797] Initializing cgroup subsys perf_event
    [ 0.120825] CPU: Physical Processor ID: 0
    [ 0.120826] CPU: Processor Core ID: 0
    [ 0.120831] ENERGY_PERF_BIAS: Set to 'normal', was 'performance'
    [ 0.120831] ENERGY_PERF_BIAS: View and update with x86_energy_perf_policy(8)
    [ 0.120834] mce: CPU supports 9 MCE banks
    [ 0.120843] CPU0: Thermal monitoring enabled (TM1)
    [ 0.120849] using mwait in idle threads.
    [ 0.121600] Switched APIC routing to physical flat.
    [ 0.121710] ExtINT not setup in hardware but reported by MP table
    [ 0.122053] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=0 pin2=0
    [ 0.132030] CPU0: Intel(R) Xeon(R) CPU X5650 @ 2.67GHz stepping 02
    [ 0.335108] Performance Events: PEBS fmt1+, Westmere events, Intel PMU driver.
    [ 0.335114] ... version: 3
    [ 0.335115] ... bit width: 48
    [ 0.335116] ... generic registers: 4
    [ 0.335117] ... value mask: 0000ffffffffffff
    [ 0.335118] ... max period: 000000007fffffff
    [ 0.335119] ... fixed-purpose events: 3
    [ 0.335120] ... event mask: 000000070000000f
    [ 0.343573] NMI watchdog enabled, takes one hw-pmu counter.
    [ 0.351083] Booting Node 0, Processors #1
    [ 0.351087] smpboot cpu 1: start_ip = 97000
    [ 0.441928] NMI watchdog enabled, takes one hw-pmu counter.
    [ 0.447825] #2
    [ 0.447827] smpboot cpu 2: start_ip = 97000
    [ 0.538666] NMI watchdog enabled, takes one hw-pmu counter.
    [ 0.544556] #3
    [ 0.544558] smpboot cpu 3: start_ip = 97000
    [ 0.635396] NMI watchdog enabled, takes one hw-pmu counter.
    [ 0.641291] #4
    [ 0.641293] smpboot cpu 4: start_ip = 97000
    [ 0.732134] NMI watchdog enabled, takes one hw-pmu counter.
    [ 0.738020] #5
    [ 0.738022] smpboot cpu 5: start_ip = 97000
    [ 0.828860] NMI watchdog enabled, takes one hw-pmu counter.
    [ 0.834751] #6
    [ 0.834753] smpboot cpu 6: start_ip = 97000
    [ 0.925576] NMI watchdog enabled, takes one hw-pmu counter.
    [ 0.931478] #7
    [ 0.931480] smpboot cpu 7: start_ip = 97000
    [ 1.022304] NMI watchdog enabled, takes one hw-pmu counter.
    [ 1.028210] #8
    [ 1.028212] smpboot cpu 8: start_ip = 97000
    [ 1.119036] NMI watchdog enabled, takes one hw-pmu counter.
    [ 1.124942] #9
    [ 1.124944] smpboot cpu 9: start_ip = 97000
    [ 1.215767] NMI watchdog enabled, takes one hw-pmu counter.
    [ 1.221673] #10
    [ 1.221676] smpboot cpu 10: start_ip = 97000
    [ 1.312501] NMI watchdog enabled, takes one hw-pmu counter.
    [ 1.318409] #11 Ok.
    [ 1.318411] smpboot cpu 11: start_ip = 97000
    [ 1.409275] NMI watchdog enabled, takes one hw-pmu counter.
    [ 1.411132] Brought up 12 CPUs
    [ 1.411135] Total of 12 processors activated (63991.89 BogoMIPS).
    [ 1.419679] devtmpfs: initialized
    [ 1.449907] PM: Registering ACPI NVS region at bf7b9000 (4096 bytes)
    [ 1.450050] print_constraints: dummy:
    [ 1.450079] RTC time: 9:49:07, date: 06/27/12
    [ 1.450140] NET: Registered protocol family 16
    [ 1.450359] PCI: Using configuration type 1 for base access
    [ 1.462855] bio: create slab <bio-0> at 0
    [ 1.462968] ACPI: Interpreter disabled.

  4. #4
    Join Date
    Jun 2008
    Location
    Kansas City Area, Missouri, USA
    Posts
    7,235

    Default Re: KVM shows wrong number of CPU's

    On 06/28/2012 11:36 AM, senblue wrote:
    >
    > lwfinger;2471612 Wrote:


    >> You should compare the two versions of dmesg for a clue regarding why
    >> the
    >> desktop only sees half of the CPUs. It may be a kernel bug.

    >
    >
    > I dont want to spam this board with excessive listings
    > therefore below only some of the output of dmesg concerning cpus.


    If you read carefully, I never asked for you to post the dmesg output, but
    recommended that you look at it carefully.

    > Booting an ubuntu-12.04-live-system with kernel 3.2.0-23-generic
    > gives me the 24 cpus like the xen-kernel of opensuse 12.1.


    Obviously, that kernel bug was fixed between 3.1.0 and 3.2.0. You need to
    implement a later version, either by installing one from the openSuSE kernel
    repos, or by downloading the kernel source for 3.4.4 and building your own kernel.

  5. #5

    Default Re: KVM shows wrong number of CPU's

    Quote Originally Posted by lwfinger View Post
    On 06/28/2012 11:36 AM, senblue wrote:
    >
    > lwfinger;2471612 Wrote:


    >> You should compare the two versions of dmesg for a clue regarding why
    >> the
    >> desktop only sees half of the CPUs. It may be a kernel bug.

    >
    >
    > I dont want to spam this board with excessive listings
    > therefore below only some of the output of dmesg concerning cpus.


    If you read carefully, I never asked for you to post the dmesg output, but
    recommended that you look at it carefully.

    I thought the with the (minimal) dmesg output you or somebody
    else would get a clue what is wrong.


    > Booting an ubuntu-12.04-live-system with kernel 3.2.0-23-generic
    > gives me the 24 cpus like the xen-kernel of opensuse 12.1.


    Obviously, that kernel bug was fixed between 3.1.0 and 3.2.0. You need to
    implement a later version, either by installing one from the openSuSE kernel
    repos, or by downloading the kernel source for 3.4.4 and building your own kernel.

    Unfortunately it seemed not to b a kernel bug. I installed kernel-default-3.4.4-1.1.x86_64.rpm
    and the problem remains.
    I read the dmesg output, found the line:
    0.000000] setup_percpu: NR_CPUS:512 nr_cpumask_bits:512 nr_cpu_ids:12 nr_node_ids:1

    The NR_CPUS expands to CONFIG_NR_CPUS in the kernel-config. But i did not find something
    like CONFIG_NR_CPU_IDS. After some googling i assumed that its somehow related to or controlled
    by acpi. Since my machine is booted with "acpi=off" i changed that and voila got the
    full numeber of 24 cpus.
    But acpi was off for a reason (unpredictable server freezes). So i will give acpi=ht a shot.
    It should disable ACPI system almost completely, but allows hyperthreading.

    I wonder why the xen-kernel gives me my full 24 cpus in spite of acpi=off.
    It must be some kernel-configuration i am not aware of. And i think there is lot of it :-( .

  6. #6
    Join Date
    Jun 2008
    Location
    Kansas City Area, Missouri, USA
    Posts
    7,235

    Default Re: KVM shows wrong number of CPU's

    On 06/29/2012 10:36 AM, senblue wrote:
    >
    > lwfinger;2471785 Wrote:
    >> On 06/28/2012 11:36 AM, senblue wrote:
    >>>
    >>> lwfinger;2471612 Wrote:

    >>
    >>>> You should compare the two versions of dmesg for a clue regarding

    >> why
    >>>> the
    >>>> desktop only sees half of the CPUs. It may be a kernel bug.
    >>>
    >>>
    >>> I dont want to spam this board with excessive listings
    >>> therefore below only some of the output of dmesg concerning cpus.

    >>
    >> If you read carefully, I never asked for you to post the dmesg output,
    >> but
    >> recommended that you look at it carefully.
    >>
    >> I thought the with the (minimal) dmesg output you or somebody
    >> else would get a clue what is wrong.
    >>
    >>> Booting an ubuntu-12.04-live-system with kernel 3.2.0-23-generic
    >>> gives me the 24 cpus like the xen-kernel of opensuse 12.1.

    >>
    >> Obviously, that kernel bug was fixed between 3.1.0 and 3.2.0. You need
    >> to
    >> implement a later version, either by installing one from the openSuSE
    >> kernel
    >> repos, or by downloading the kernel source for 3.4.4 and building your
    >> own kernel.

    >
    >
    > Unfortunately it seemed not to b a kernel bug. I installed
    > kernel-default-3.4.4-1.1.x86_64.rpm
    > and the problem remains.
    > I read the dmesg output, found the line:
    > 0.000000] setup_percpu: NR_CPUS:512 nr_cpumask_bits:512 nr_cpu_ids:12
    > nr_node_ids:1
    > CONFIG_NR_CPUS
    > The NR_CPUS expands to CONFIG_NR_CPUS in the kernel-config. But i did
    > not find something
    > like CONFIG_NR_CPU_IDS. After some googling i assumed that its somehow
    > related to or controlled
    > by acpi. Since my machine is booted with "acpi=off" i changed that and
    > voila got the
    > full numeber of 24 cpus.
    > But acpi was off for a reason (unpredictable server freezes). So i will
    > give acpi=ht a shot.
    > It should disable ACPI system almost completely, but allows
    > hyperthreading.


    The CONFIG_NR_CPUS parameter controls the maximum number that are allowed. The
    discovery process while booting tells you how many there are. The standard
    setting for the kernel parameter CONFIG_SCHED_SMT is "y", thus they should be
    enabled.

    The thread at http://www.gossamer-threads.com/list...kernel/1182330 has
    some discussion on the value of enabling the HT pseudo-CPUs.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •