Re: [PATCH v5 0/4] perf stat: Introduce iostat mode to provide I/O performance metrics

[Namhyung Kim]

Hello,

On Wed, Mar 24, 2021 at 11:30 PM Alexander Antonov
<alexander.antonov@xxxxxxxxxxxxxxx> wrote:
>
> The previous version can be found at:
> v4: https://lkml.kernel.org/r/20210203135830.38568-1-alexander.antonov@xxxxxxxxxxxxxxx/
> Changes in this revision are:
> v4 -> v5:
> - Addressed comments from Namhyung Kim:
>   1. Removed AGGR_PCIE_PORT aggregation mode
>   2. Added iostat_prepare() function
>   3. Moved implementation specific fprintf() calls to separate x86-related function
>   4. Fixed code-related issues
> - Moved __weak iostat's functions to separate util/iostat.c file
>
> The previous version can be found at:
> v3: https://lkml.kernel.org/r/20210126080619.30275-1-alexander.antonov@xxxxxxxxxxxxxxx/
> Changes in this revision are:
> v3 -> v4:
> - Addressed comment from Namhyung Kim:
>   1. Removed NULL-termination of root ports list
>
> The previous version can be found at:
> v2: https://lkml.kernel.org/r/20201223130320.3930-1-alexander.antonov@xxxxxxxxxxxxxxx
>
> Changes in this revision are:
> v2 -> v3:
> - Addressed comments from Namhyung Kim:
>   1. Removed perf_device pointer from evsel structure. Use priv field instead
>   2. Renamed 'iiostat' to 'iostat'
>   3. Renamed 'show' mode to 'list' mode
>   4. Renamed iiostat_delete_root_ports() to iiostat_release() and
>      iostat_show_root_ports() to iostat_list()
>
> The previous version can be found at:
> v1: https://lkml.kernel.org/r/20201210090340.14358-1-alexander.antonov@xxxxxxxxxxxxxxx
>
> Changes in this revision are:
> v1 -> v2:
> - Addressed comment from Arnaldo Carvalho de Melo:
>   1. Using 'perf iiostat' subcommand instead of 'perf stat --iiostat':
>     - Added perf-iiostat.sh script to use short command
>     - Updated manual pages to get help for 'perf iiostat'
>     - Added 'perf-iiostat' to perf's gitignore file
>
> Mode is intended to provide four I/O performance metrics in MB per each
> 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)
>
> Note: iostat introduces new perf data aggregation mode - per PCIe root port
> hence -e and -M options are not supported.
>
> Usage 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
>
> Alexander Antonov (4):
>   perf stat: Basic support for iostat in perf
>   perf stat: Helper functions for PCIe root ports list in iostat mode
>   perf stat: Enable iostat mode for x86 platforms
>   perf: Update .gitignore file

Thanks for your work!

Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Thanks,
Namhyung


>
>  tools/perf/.gitignore                    |   1 +
>  tools/perf/Documentation/perf-iostat.txt |  88 +++++
>  tools/perf/Makefile.perf                 |   5 +-
>  tools/perf/arch/x86/util/Build           |   1 +
>  tools/perf/arch/x86/util/iostat.c        | 470 +++++++++++++++++++++++
>  tools/perf/builtin-stat.c                |  21 +-
>  tools/perf/command-list.txt              |   1 +
>  tools/perf/perf-iostat.sh                |  12 +
>  tools/perf/util/Build                    |   1 +
>  tools/perf/util/iostat.c                 |  53 +++
>  tools/perf/util/iostat.h                 |  47 +++
>  tools/perf/util/stat-display.c           |  40 +-
>  tools/perf/util/stat-shadow.c            |   5 +-
>  tools/perf/util/stat.h                   |   1 +
>  14 files changed, 733 insertions(+), 13 deletions(-)
>  create mode 100644 tools/perf/Documentation/perf-iostat.txt
>  create mode 100644 tools/perf/arch/x86/util/iostat.c
>  create mode 100644 tools/perf/perf-iostat.sh
>  create mode 100644 tools/perf/util/iostat.c
>  create mode 100644 tools/perf/util/iostat.h
>
>
> base-commit: 6859bc0e78c6a699599cbb21404fdb6c8125da74
> --
> 2.19.1
>