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Vtune 2015.4 and CPU Frequency Ratio

iceecp
Beginner
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Hi,

I have used Vtune 2015.4 to perform an 'Advanced Hotspots' analysis for a sequential code on a Haswell processor (CentOS release 6.6).

The line "CPU Frequency Ratio"  ("The ratio between the actual and nominal Values of
CPU frequencies. Values above 1 indicate that the CPU operates in a turbo boost mode") indicates "1.130" (see attached file)

Vtune indicates that the node that is used is "r1i0n10" that "Frequency" (nominal ?) is 2.30Ghz.

As I understand, the CPU has reached an actual frequency of 2.3*1.130=2.5990Ghz ?

However, If I look at the node, I have for the frequency

[root@r1i0n10 ~]# cpupower frequency-info  -o
          minimum CPU frequency  -  maximum CPU frequency  -  governor
CPU  0      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  1      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  2      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  3      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  4      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  5      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  6      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  7      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  8      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU  9      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 10      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 11      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 12      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 13      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 14      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 15      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 16      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 17      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 18      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 19      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 20      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 21      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 22      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand
CPU 23      1200000 kHz ( 52 %)  -    2301000 kHz (100 %)  -  ondemand

Since I did not ask for any variation of the CPU frequency when launching the code (and "maximum frequency" is 2.301Ghz), I don't understand why Vtune suggests that "the CPU operates in a turbo boost mode" with an actual frequency of 2.3*1.130=2.5990Ghz.

Could you help me understand this result please ?

All the best,

Anne-Sophie

 

 

 

 

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