On Fri, 2003-11-14 at 08:41, Takeshi Sone wrote:
On Fri, Nov 14, 2003 at 08:26:55AM +0100, Svante Signell wrote:
For the erroneous motherboard with a 1.3GHz Tualatin CPU the numbers are around 400ns independent of array size. The only thing changig is that the latency numbers increase to 440-460ns for large values of the stride. My interpretation is that not even the L1 cache is working properly. All other tests indicate a _very_ slow CPU, around 7MHz is measured by lmbench (BTW how good is this value?) compared to the expected 1.3GHz. Two questions immediately arise.
- Is this slowness reasonable if _no- caches are working properly?
- If there is a problem with the on-chip voltage regulator and the CPU
clock speed is really 7MHz, as measured by lmbench, can the CPU operate properly at this low speed. I thought there was a _lower_ limit as well as an upper limit for the operating frequency?
What do these commands say?
cat /proc/mtrr cat /proc/cpuinfo
Normal output: 1.4GHz Tualatin cat/proc/mtrr: reg00: base=0x00000000 ( 0MB), size= 256MB: write-back, count=1 reg01: base=0xe4000000 (3648MB), size= 8MB: write-combining, count=1
# Faulty system: cat /proc/mtrr cat: /proc/mtrr: No such file or directory
Faulty system: $ cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 11 model name : Intel(R) Celeron(TM) CPU 1300MHz stepping : 4 cpu MHz : 1340.197 cache size : 256 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 mmx fxsr sse bogomips : 2641.10