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We are looking for a way to estimate the actual memory bandwidth on a POWER7 system using the hardware counters.
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2 replies Latest Post - 2011-05-10T20:41:10Z by SystemAdmin
Pinned topic POWER7 PMCs: Is there a way to estimate memory bandwidth using PMU events?
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Updated on 2011-05-10T20:41:10Z at 2011-05-10T20:41:10Z by SystemAdmin
Re: POWER7 PMCs: Is there a way to estimate memory bandwidth using PMU events?2011-05-04T19:01:32Z in response to SystemAdminAnd as always with hardware counters, there's a "it depends" answer emerging.
Code examples are being built with two counters. The actual derived (estimated) bandwidth would be a formula which is being validated.
PM_MEM0_RQ_DISP - Event counted at memory controller to count memory read dispatches PM_MEM0_WQ_DISP - Event counted at memory controller to count memory write dispatches
Re: POWER7 PMCs: Is there a way to estimate memory bandwidth using PMU events?2011-05-10T20:41:10Z in response to SystemAdminAs an update.. there is some peculiar initial behavior with these counters when measuring fairly simple applications. In other words, the pieces are not yet adding up when using "perf". Investigations continue. If you happen to be working in this area and have your own observations, we would like to hear from you.