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111alan
Adept I

Measuring Cache hit rate in uprof?

Was trying to get some basic performance data in uprof. My question is, how to calculate the actual hit rate of uop/L1/L2/L3 cache? The results of simply making divisions between the DC_refill_L2/CCX/dram values doesn't seem to make sense(too high).

 

And what does function "%data cache miss" actually mean? Is it the proportion of accesses that missed all levels of caches, or it's just the percentage that missed the L1D?uprof.JPG

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1 Solution
swarup
Staff

Hi 111alan‌,

L1D Hit rate can be calculated from (L1) DC Miss rate (event 0x60, umask 0xC8). DC Miss rate can be seen by selecting "View" dropdown box > "Data access assessment".
L2 Hits can be calculated by profiling the event 0x64, umask=0xF6.
As L3 is shared among group of cores, uProf does not support L3 specific events. For that, you may need to use AMDPcm tool packed along with uProf.


"%data cache miss" :  It is the percentage that missed the L1D.

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1 Reply
swarup
Staff

Hi 111alan‌,

L1D Hit rate can be calculated from (L1) DC Miss rate (event 0x60, umask 0xC8). DC Miss rate can be seen by selecting "View" dropdown box > "Data access assessment".
L2 Hits can be calculated by profiling the event 0x64, umask=0xF6.
As L3 is shared among group of cores, uProf does not support L3 specific events. For that, you may need to use AMDPcm tool packed along with uProf.


"%data cache miss" :  It is the percentage that missed the L1D.