Hello, I am measuring the PMC 0xF2 to get the evictions from the L2 to the L3 due to DEMAND REQUEST and from the L2 HW PREF. In each source, the evictions are reported for CLEAN and DIRTY lines. What I don't understand is the L3 is inclusive of the data in the L1 or L2, so why are we evicting CLEAN lines to the L3. If you look and measure the PMC data on PMC 0xF0 you can monitor all L2 -> L3 writebacks, that number does not include the evictions of CLEAN lines but rather the DIRTY component. On SandyBridge, do you evict clean L2 lines to the L3, I don't believe so, right? If you don't, then why in Table A2 of the System Prog Guide, do you state PMC 0xF2 umask=0x01,0x04 are measures of this activity?Thanks for any clarification..perfwise
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