Hi Jonathan, Do you have any comments about this proposal?
Thanks, -Aubrey Li, Aubrey wrote: > >Jonathan Chew wrote: >> >>Thanks for summarizing the metrics. However, I wanted to see a summary >>of the overall NUMAtop proposal given the feedback that you have gotten, >>so I can understand what the project is proposing to do now that you >>have gotten feedback. Then I can decide whether I have anything to add >>and whether I want to approve it as is or not. >> >> From the email thread so far, it looks as though Krish gave a very >>brief description of the project, Jin Yao explained some phases for the >>project, and you have listed some proposed metrics for the tool >> >>Have anything of these changed given the feedback that you have gotten? >>Can you please summarize your latest project proposal including the >>description, phases, metrics, and anything else that is useful for >>understanding what the project is proposing to do? >> >> >>Jonathan > >NUMAtop focus on NUMA-related characteristic, it's a tool to help >developers >identify memory locality in NUMA systems. The tool is top-like that >shows >the top N processes in the system and their memory locality, with those >processes >that have the worst memory locality will be at the top of the list, it >can >attach into a process to show the threads memory locality in the top >style as well. > >The information NUMAtop reported is collected from memory-related >hardware >counters and libcpc Dtrace provider. Some of these counters are already >supported >in kcpc and libcpc, while some of them are not. Intel Nehalem-based and >next-generation platform provide memory load latency event, which is an >important approach of NUMAtop and needs PEBS framework solaris >implementation. > >The following proposed metrics will be one part of our phase I job. >Application can be classified into CPU-sensitive, Memory-sensitive, IO- >sensitive. >IO-sensitive application can be idendified by low CPU utilization. >Memory-sensitive >application should be CPU-sensitive application with high CPU >utilization. > >So we have the following metrics: > >1) sysload - cpu sensitive >2) LLC Miss per Instruction - memory sensitive > >After we figure out the application is memory-sensitive, we'll check >memory locality >metrics to see what is the performance regression cause. > >3) LLC Latency Ratio(Average Latency for LLC Miss/Local Memory Access >Latency) >4) Source distribution for LLC miss: > -4.1)LMA/(Total LLC Miss Retired)% > -4.2)RMA/(Total LLC Miss Retired)% > >Here, 4.2) could be separated into different % onto different NUMA node >hop. > >NUMAtop should have a useful report to show how effective the >application is using the >local memory. We need PEBS framework to implement the metrics of NUMATOP, >We need MPO >sponsor and libcpc dtrace provider sponsor to figure out where is not >effective and why. >A better memory placement strategy suggestion is also a valuable goal of >NUMATOP. > >Thanks, >-Aubrey >_______________________________________________ >perf-discuss mailing list >perf-discuss@opensolaris.org _______________________________________________ perf-discuss mailing list perf-discuss@opensolaris.org
