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diff --git a/tools/perf/Documentation/perf-iostat.txt b/tools/perf/Documentation/perf-iostat.txt new file mode 100644 index 000000000..04d510364 --- /dev/null +++ b/tools/perf/Documentation/perf-iostat.txt @@ -0,0 +1,88 @@ +perf-iostat(1) +=============== + +NAME +---- +perf-iostat - Show I/O performance metrics + +SYNOPSIS +-------- +[verse] +'perf iostat' list +'perf iostat' <ports> \-- <command> [<options>] + +DESCRIPTION +----------- +Mode is intended to provide four I/O performance metrics per each PCIe root port: + +- Inbound Read - I/O devices below root port read from the host memory, in MB + +- Inbound Write - I/O devices below root port write to the host memory, in MB + +- Outbound Read - CPU reads from I/O devices below root port, in MB + +- Outbound Write - CPU writes to I/O devices below root port, in MB + +OPTIONS +------- +<command>...:: + Any command you can specify in a shell. + +list:: + List all PCIe root ports. + +<ports>:: + Select the root ports for monitoring. Comma-separated list is supported. + +EXAMPLES +-------- + +1. List all PCIe root ports (example for 2-S platform): + + $ perf iostat list + S0-uncore_iio_0<0000:00> + S1-uncore_iio_0<0000:80> + S0-uncore_iio_1<0000:17> + S1-uncore_iio_1<0000:85> + S0-uncore_iio_2<0000:3a> + S1-uncore_iio_2<0000:ae> + S0-uncore_iio_3<0000:5d> + S1-uncore_iio_3<0000:d7> + +2. Collect metrics for all PCIe root ports: + + $ perf iostat -- dd if=/dev/zero of=/dev/nvme0n1 bs=1M oflag=direct + 357708+0 records in + 357707+0 records out + 375083606016 bytes (375 GB, 349 GiB) copied, 215.974 s, 1.7 GB/s + + Performance counter stats for 'system wide': + + port Inbound Read(MB) Inbound Write(MB) Outbound Read(MB) Outbound Write(MB) + 0000:00 1 0 2 3 + 0000:80 0 0 0 0 + 0000:17 352552 43 0 21 + 0000:85 0 0 0 0 + 0000:3a 3 0 0 0 + 0000:ae 0 0 0 0 + 0000:5d 0 0 0 0 + 0000:d7 0 0 0 0 + +3. Collect metrics for comma-separated list of PCIe root ports: + + $ perf iostat 0000:17,0:3a -- dd if=/dev/zero of=/dev/nvme0n1 bs=1M oflag=direct + 357708+0 records in + 357707+0 records out + 375083606016 bytes (375 GB, 349 GiB) copied, 197.08 s, 1.9 GB/s + + Performance counter stats for 'system wide': + + port Inbound Read(MB) Inbound Write(MB) Outbound Read(MB) Outbound Write(MB) + 0000:17 358559 44 0 22 + 0000:3a 3 2 0 0 + + 197.081983474 seconds time elapsed + +SEE ALSO +-------- +linkperf:perf-stat[1] |