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does vtune support CPI for each line of source code?

softarts
Beginner
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can vtune letsme examine the cycles per instruction (CPI) for each line of source code?
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Vladimir_T_Intel
Moderator
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Quoting - softarts
can vtune letsme examine the cycles per instruction (CPI) for each line of source code?

Hi,

VTune does not calculate CPI per source line just because there is no much sense in that. CPI is integral characteristic, that reflects statistically correct ratio regarding a group of hot instructions, like loop or function (or on higher level - module or process). However, you can calculate CLI against a source line having clockticks and instructions retired event numbers collected for it.

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srimks
New Contributor II
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Quoting - softarts
can vtune lets me examine the cycles per instruction (CPI) for each line of source code?

Please read my earlier postings for CPI http://software.intel.com/en-us/forums/showthread.php?t=63984

There is Getting_Started Guide on VTune which helps pretty much as a beginner. I referred David Levinthal paper as published http://assets.devx.com/goparallel/18027.pdf , it gives good idea to distinguish CPI & other cycles related to Cache misses, DTLB misses, Branch-MisPredictions, etc.
Also, would like to suggest reading "Intel Itanium Processor Reference Manual" as an information for Processor internals and VTune flow http://download.intel.com/design/Itanium2/manuals/25111003.pdf . But the events of Itanium need not be same with any Intel Xeon processors events, simply suggesting above "Intel Itanium Processor refernce manual" because VTune is very descriptive with this processor and tiil date Intel haven't brought similar document w.r.t Intel Xeon processors.

I think both these are good stuffs to start working with VTune in depth and knowing about CPI and other cycles events.

Do refer: http://assets.devx.com/goparallel/18027.pdf
http://software.intel.com/en-us/articles/using-intel-vtune-performance-analyzer-events-ratios-optimizing-applications/

~BR
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