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Why QPI traffic captured by PCM is larger than bandwith of QPI port?

li_y_1
Beginner
134 Views

Hi ,

    I meet a porblem when using PCM V2.11. The QPI frequency is 9.6Gb/s. Why the QPI traffic is larger than 19.2, and the ration is so small?

BRs,

=================================================================================

Intel(r) QPI traffic estimation in bytes (data and non-data traffic outgoing from CPU/socket through QPI links):

               QPI0     QPI1     QPI2    |  QPI0   QPI1   QPI2 
---------------------------------------------------------------------------------------------------------------
 SKT    0       26 G     32 G     28 G   |   27%    34%    29%  
 SKT    1       34 G     30 G     26 G   |   36%    31%    27%  
 SKT    2       33 G     34 G     32 G   |   35%    36%    34%  
 SKT    3       30 G     38 G     29 G   |   32%    39%    30%  
---------------------------------------------------------------------------------------------------------------

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2 Replies
Roman_D_Intel
Employee
134 Views

Hi,

PCM reports absolute values for the measured time interval. It does not normalize them (per second).

Best regards,

Roman

li_y_1
Beginner
134 Views

Hi Roman:

       Is the utilization of QPI based on the QPI frequency? Take "QPI0 27%" as example. Does it mean the average thoughtput of QPI0  is 27% compared with 19.2GB/S ?

BRs,

LiYing

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