Why DMA is not listed in windows performance monitor's available counters? RDMA Activity is already present but not DMA. Is it possible to monitor DMA in windows?
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What useful information to you expect to gain by "monitor[ing] DMA in windows"? (HINT: it's a rhetorical question.)– sawdustNov 16, 2017 at 21:26
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1Most of what's in that list is going to be information that is actually useful to diagnose a problem, like overall high CPU usage or slow disk transfers. What does DMA give you that all the other measures do not or cannot measure more easily with less overhead? Tracking DMA is likely to be difficult from a CPU perspective as you'll only get a vague time of when it started and finished but you can't do anything "in real time"... Program counters are going to be one of those useless measures as well and profiling all the thread statistics to the n-th degree will be more overhead than anything.– Mokubai ♦Nov 16, 2017 at 21:50
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@Aryan -- No, my question to you was rhetorical. As Mokubai points out in agreement, DMA statistics (whatever that might be) are not useful. To obtain any accurate numbers, the computer would need additional circuitry. Any effort to gather stats using software consumes CPU cycles at crucial interrupt level, and delays subsequent DMA operations. But again, what purpose would such stats have?– sawdustNov 16, 2017 at 22:03
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@sawdust Our paper on understanding RDMA networking performance (usenix.org/system/files/conference/atc16/atc16_paper-kalia.pdf) discusses a use case of DMA counters.– Anuj KaliaNov 17, 2017 at 5:28
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1 Answer
Have you tried Intel's PCM https://software.intel.com/en-us/articles/intel-performance-counter-monitor? I've used it to monitor DMA activity on Linux.
