PERF-IOSTAT(1) | perf Manual | PERF-IOSTAT(1) |
NAME
perf-iostat - Show I/O performance metrics
SYNOPSIS
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
2021-08-10 | perf |