/proc/cpuinfo shows cpu Mhz :0.000

apalkar · 07-17-2007, 01:17 PM

Hi,

I have recently started using Linux Red Hat 3.4.5-2. I have a program that reads the /proc/cpuinfo file and it expects the cpu Mhz field in the file to be a non-zero value (which should be the case). But when I checked the file this is what I got:

ade:[ apalkar_alhad ] [apalkar@sta00144 skgxpg]$ cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 65
model name : Dual-Core AMD Opteron(tm) Processor 2216
stepping : 2
cpu MHz : 0.000
cache size : 1024 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx mmxext lm 3dnowext 3dnow pni
bogomips : 1191.93

The cpu Mhz field is 0. Can anybody tell me why this might be happening?

Thanks
Alhad.

bulliver · 07-18-2007, 03:23 PM

Hi.

Is dmesg giving you the same value?
Anyway, I would look closely at your kernel configuration, specifically the "Processor type and features" section. For one thing, your dual core should show up as two processors. Make sure you have "Symmetric multi-processing support" enabled. Make sure processor family is set to "Opteron/Athlon64/Hammer/K8"

You may also want to make sure that everything is kosher in your BIOS setup screen, as the kernel certainly seems to be having problems detecting your CPU correctly.

HTH

apalkar · 07-18-2007, 05:11 PM

Hi,

Thanks for the reply. I cannot see anything in the dmesg output that might be the cpu clock speed value. I have a couple more questions.

1. How do I make sure the SMP support has been enabled?
and Proc Family is set to Opteron/Athlon64/Hammer/K8.

One thing I would like to mention is that I am remote logging to
the linux box and I dont think I have admin rights for it.

2. You mentioned that I should check whether everything is "kosher"
in the BIOS setup. Can you kindly explain what do u mean by that
term. Havn't heard it before in this context.

Thanks
Alhad.

HappyTux · 07-18-2007, 05:44 PM

Quote:

Originally Posted by apalkar

Hi,

Thanks for the reply. I cannot see anything in the dmesg output that might be the cpu clock speed value. I have a couple more questions.

Use a command like below.

Code:

dmesg | grep time.c
time.c: Detected 2799.995 MHz processor.

Quote:

1. How do I make sure the SMP support has been enabled?
and Proc Family is set to Opteron/Athlon64/Hammer/K8.

You should see two processor in the cat /proc/cpuinfo command like below.

Code:

cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Intel(R) Core(TM)2 CPU          6300  @ 1.86GHz
stepping        : 6
cpu MHz         : 2799.995
cache size      : 2048 KB
physical id     : 0
siblings        : 2
core id         : 0
cpu cores       : 2
fpu             : yes
fpu_exception   : yes
cpuid level     : 10
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr lahf_lm
bogomips        : 5602.82
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

processor       : 1
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Intel(R) Core(TM)2 CPU          6300  @ 1.86GHz
stepping        : 6
cpu MHz         : 2799.995
cache size      : 2048 KB
physical id     : 0
siblings        : 2
core id         : 1
cpu cores       : 2
fpu             : yes
fpu_exception   : yes
cpuid level     : 10
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr lahf_lm
bogomips        : 5599.85
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

Now not seeing this in your output means you do not have SMP enabled plus if you look at your bogomips you have roughly a 600mhz processor running as it is usually 2 x processor speed on any machine I have ever run linux on.

Quote:

One thing I would like to mention is that I am remote logging to
the linux box and I dont think I have admin rights for it.

That sucks kind of hard doing any real repair work if you don't have physical access to the box it would be hard enough with root on a remote machine for what you need to do.

Quote:

2. You mentioned that I should check whether everything is "kosher"
in the BIOS setup. Can you kindly explain what do u mean by that
term. Havn't heard it before in this context.

Thanks
Alhad.

I would say he means making sure the bus speeds are set properly looking at the CPU information to see if the processor is detected properly in the BIOS, see what version the BIOS is at as maybe it needs upgrade. Oh and if the fourth response on this page is what you have running then a 2.6.9 kernel is way too old to be running on the kind of hardware you have.

syg00 · 07-18-2007, 08:09 PM

Easist to grep the (kernel) config file for features like SMP - hopefully in /boot, or see if /proc/config.gz exists. (do the greps as -i else you'll miss things)

Edit: Just found an old Centos config - there is separate config file for SMP; implies separate kernels. Check you are using the correct one.

apalkar · 07-19-2007, 03:13 PM

Quote:

Originally Posted by syg00

Easist to grep the (kernel) config file for features like SMP - hopefully in /boot, or see if /proc/config.gz exists. (do the greps as -i else you'll miss things)

Edit: Just found an old Centos config - there is separate config file for SMP; implies separate kernels. Check you are using the correct one.

Hi,

/proc/config.gz does not exist on my system. Do you know the specific files in /boot that might contain the information. What are the strings I should be greping for in /boot?

One more thing. I did a ps aux on my system, and a vmware backgnd process seems to be running:

Code:

[apalkar@sta00144 ~]$ ps aux | grep vm
root      1944  0.0  0.0     0    0 ?        S    May22   0:01 [vmmemctl]
root      1969  0.0  0.0  1588  608 ?        Ss   May22   3:32 /usr/sbin/vmware-
guestd --background /var/run/vmware-guestd.pid
apalkar   4855  0.0  0.0  4476  692 pts/0    S+   13:11   0:00 grep vm

Do you think this might be causing problems with cpuinfo?

Thanks
Alhad.

apalkar · 07-19-2007, 03:16 PM

Hi,

I tried dmesg | grep time.c, but it didnt come up with anything. Is there any other method to find the cpu clock freq if /proc/cpuinfo and dmesg cannot do it?

Thanks
Alhad.

syg00 · 07-20-2007, 04:53 AM

Quote:

Originally Posted by apalkar

/proc/config.gz does not exist on my system. Do you know the specific files in /boot that might contain the information. What are the strings I should be greping for in /boot?

The config.gz is optional - it's specified in the .config ....

Any config (in /boot) should be obvious - hopefully something like config-`uname -r`.

Quote:

One more thing. I did a ps aux on my system, and a vmware backgnd process seems to be running:

Do you think this might be causing problems with cpuinfo?

I doubt it.
All the virtuals I looked at showed the correct values.

apalkar · 07-20-2007, 12:39 PM

Hi,

I got a reply from the support team. They said it is because the machine is running vmware. I checked my frnds m/c too. His cpu Mhz is also showing up as 0.000; and he has vmware running on his m/c.

Thanks a lot for the help.

Alhad.