leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

perf stat: Enable iostat mode for x86 platforms

Browse Source 
This functionality is based on recently introduced sysfs attributes for
Intel® Xeon® Scalable processor family (code name Skylake-SP):

Commit bb42b3d397 ("perf/x86/intel/uncore: Expose an Uncore unit to IIO PMON mapping")

Mode is intended to provide four I/O performance metrics in MB per each
PCIe root port:

 - Inbound Read: I/O devices below root port read from the host memory
 - Inbound Write: I/O devices below root port write to the host memory
 - Outbound Read: CPU reads from I/O devices below root port
 - Outbound Write: CPU writes to I/O devices below root port

Each metric requiries only one uncore event which increments at every 4B
transfer in corresponding direction. The formulas to compute metrics
are generic:
    #EventCount * 4B / (1024 * 1024)

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey V Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210419094147.15909-4-alexander.antonov@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Alexander Antonov
2021-04-19 12:41:46 +03:00
committed by Arnaldo Carvalho de Melo
parent 19776d3ced
commit f9ed693e8b
6 changed files with 466 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

88
tools/perf/Documentation/perf-iostat.txt Normal file
View File

@@ -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]