tareqsiraj Posted September 15, 2008 Share Posted September 15, 2008 Hello everyone, I have this Quad Quad-core machine running Hardy x86_64. Unfortunately, its only detecting 8 cores out of 16 cores. I tried a Fedora 8 x86_64 installation disk and did a cat /proc/cpuinfo in a ternimal and it detected all 16 cores. Do I need to enable any kernel flags when booting Hardy? Thanks in advance. $ uname -a Linux moriyama 2.6.24-19-generic #1 SMP Wed Aug 20 17:53:40 UTC 2008 x86_64 GNU/Linux $ cat /proc/cpuinfo | grep processor processor : 0 processor : 1 processor : 2 processor : 3 processor : 4 processor : 5 processor : 6 processor : 7 $ sudo lshw -C cpu [sudo] password for tsiraj: *-cpu:0 description: CPU product: Quad-Core AMD Opteron(tm) Processor 8354 vendor: Advanced Micro Devices [AMD] physical id: 3 bus info: cpu@0 version: 15.2.3 serial: To Be Filled By O.E.M. slot: CPU 1 size: 2200MHz capacity: 2200MHz width: 64 bits clock: 200MHz capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp x86-64 3dnowext 3dnow constant_tsc rep_good pni cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs *-cpu:1 description: CPU product: Quad-Core AMD Opteron(tm) Processor 8354 vendor: Advanced Micro Devices [AMD] physical id: 8 bus info: cpu@1 version: 15.2.3 serial: To Be Filled By O.E.M. slot: CPU 2 size: 2200MHz capacity: 2200MHz width: 64 bits clock: 200MHz capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp x86-64 3dnowext 3dnow constant_tsc rep_good pni cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs *-cpu:2 description: CPU product: (To Be Filled By O.E.M.) vendor: AMD physical id: 4 bus info: cpu@2 version: 15.2.3 serial: To Be Filled By O.E.M. slot: CPU 3 size: 2200MHz capacity: 2200MHz clock: 200MHz *-cpu:3 description: CPU product: (To Be Filled By O.E.M.) vendor: AMD physical id: 10 bus info: cpu@3 version: 15.2.3 serial: To Be Filled By O.E.M. slot: CPU 4 size: 2200MHz capacity: 2200MHz clock: 200MHz *-cpu:4 UNCLAIMED physical id: 7 bus info: cpu@4 version: 15.2.3 <snip /> *-cpu:14 UNCLAIMED physical id: 14 bus info: cpu@14 version: 15.2.3 Link to comment Share on other sites More sharing options...
tareqsiraj Posted September 15, 2008 Author Share Posted September 15, 2008 update... dmesg says its ignoring the missing 8 :(. Is there any limit on this? tsiraj@moriyama: ~ $ dmesg | grep CPU [ 0.000000] Processor #0 (Bootup-CPU) [ 0.000000] WARNING: NR_CPUS limit of 8 reached. Processor ignored. [ 0.000000] WARNING: NR_CPUS limit of 8 reached. Processor ignored. [ 0.000000] WARNING: NR_CPUS limit of 8 reached. Processor ignored. [ 0.000000] WARNING: NR_CPUS limit of 8 reached. Processor ignored. [ 0.000000] WARNING: NR_CPUS limit of 8 reached. Processor ignored. [ 0.000000] WARNING: NR_CPUS limit of 8 reached. Processor ignored. [ 0.000000] WARNING: NR_CPUS limit of 8 reached. Processor ignored. [ 0.000000] WARNING: NR_CPUS limit of 8 reached. Processor ignored. [ 0.000000] SMP: Allowing 8 CPUs, 0 hotplug CPUs [ 0.000000] PERCPU: Allocating 34656 bytes of per cpu data [ 0.000000] Initializing CPU#0 [ 55.975125] CPU 0: aperture @ c000000 size 32 MB [ 56.289524] SLUB: Genslabs=12, HWalign=64, Order=0-1, MinObjects=4, CPUs=8, Nodes=4 [ 56.398849] CPU: L1 I Cache: 64K (64 bytes/line), D cache 64K (64 bytes/line) [ 56.398851] CPU: L2 Cache: 512K (64 bytes/line) [ 56.398854] CPU 0/0 -> Node 0 [ 56.398856] CPU: Physical Processor ID: 0 [ 56.398857] CPU: Processor Core ID: 0 <snip /> Link to comment Share on other sites More sharing options...
Fish Posted September 15, 2008 Share Posted September 15, 2008 http://ubuntuforums.org/showthread.php?t=556602 Looks like you'll need to recompile your kernel. Link to comment Share on other sites More sharing options...
tareqsiraj Posted September 15, 2008 Author Share Posted September 15, 2008 http://ubuntuforums.org/showthread.php?t=556602Looks like you'll need to recompile your kernel. I was afraid someone is going to say that ... thanks a lot for the link. Link to comment Share on other sites More sharing options...
Mike Posted September 15, 2008 Share Posted September 15, 2008 yup the kernel is compiled with a set number of max cpu/cores to use which would apparently be set to 8 in your case Link to comment Share on other sites More sharing options...
markwolfe Veteran Posted September 15, 2008 Veteran Share Posted September 15, 2008 http://ubuntuforums.org/showthread.php?t=556602Looks like you'll need to recompile your kernel. Or use Fedora, which detected and used all cores without mucking with kernel source. Link to comment Share on other sites More sharing options...
tareqsiraj Posted September 15, 2008 Author Share Posted September 15, 2008 Or use Fedora, which detected and used all cores without mucking with kernel source. well... lets see how the recompile goes (still compiling...). I dont want to install fedora on that machine because we need a mix of different linux installations from different vendors. We already have fedora 7/8 in our build servers and we needed a server with gcc4.2, hence ubuntu. lets see how the custom kernel compilation goes first :) Link to comment Share on other sites More sharing options...
tareqsiraj Posted September 15, 2008 Author Share Posted September 15, 2008 yay ... it worked :). Thanks Mr Fish and others for your help :) Link to comment Share on other sites More sharing options...
RAID 0 Posted September 15, 2008 Share Posted September 15, 2008 yay ... it worked :). Thanks Mr Fish and others for your help :) Oh GOD! I would love to number crunch on that beast! Link to comment Share on other sites More sharing options...
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