On Thu, Jan 31, 2013 at 3:21 PM, Ingo Molnar <[email protected]> wrote: > > * Stephane Eranian <[email protected]> wrote: > >> This patchset adds a new command to perf: perf uncore. >> It is used to measure processor socket-level metrics >> on a system-wide basis and at all priv levels. >> >> The command comes with a set of predefined key metrics >> which are useful to measure multi-socket system imbalance >> and various bandwidths. >> >> The following metrics are currently defined: >> - memory bandwidth (Nehalem, Westmere, SandyBridge-EP) >> - PCIe bandwidth (SandyBridge-EP) >> - QPI bandwidth (SandyBridge-EP) >> - C-state residency (SandyBridge-EP) >> >> Others can be added in the future. >> >> The command provides options to modify the unit of the metrics >> (default: MB/s for bandwidth). >> >> Example on Nehalem: >> >> # perf uncore >> #------------------------------ >> # Socket0 | >> #------------------------------ >> # RAM Bandwidth | >> # Wr Rd| >> # MB/s MB/s| >> #------------------------------ >> 4954.99 14897.29 >> 4953.97 14894.56 >> 4947.52 14874.97 >> >> To make plotting easier, the output can be augmented with a timestamp: >> >> # perf uncore -T >> #---------------------------------------- >> # | Socket0 | >> # |------------------------------ >> # Time | RAM Bandwidth | >> # in | Wr Rd| >> # secs | MB/s MB/s| >> #---------------------------------------- >> 1 4952.50 14890.49 >> 2 4955.55 14900.19 >> 3 4949.13 14879.60 >> 4 4954.66 14896.26 > > Looks really useful - how about naming it in a bit more generic > way, because I'm quite sure this command will become popular and > 'perf uncore' is a bit un-intutive. > > A couple of possibilities: > > perf system > perf hw > perf hw-stat > I am fine with that. I prefer hw or systems for the command name.
> and also adding subcommands instead of options for the various > views/metrics, such as: > > perf hw ram > perf hw pci > perf hw qpi > perf hw cstate Yes, could do that. Even though having all of them measure at once is also useful (this is how it currently works by default). > etc. > > A plain 'perf hw' command would then list the available > sub-commands and inform the user about the (current) set of > hw subsystems that provide metrics. > Yes. this is what perf uncore -L already does. For instance on SNB-EP: $ perf uncore -L mem_bw : SNB-EP MEM Bandwidth qpi_bw : SNB-EP QPI Bandwidth pcie_bw : SNB-EP PCIe Bandwidth cstate : SNB-EP C-state residency -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
