Re: [RFC PATCH v5 4/4] test/vsock: vsock_perf utility

[Stefano Garzarella]

On Tue, Dec 20, 2022 at 07:23:46AM +0000, Arseniy Krasnov wrote:
> This adds utility to check vsock rx/tx performance.
>
> Usage as sender:
> ./vsock_perf --sender <cid> --port <port> --bytes <bytes to send>
> Usage as receiver:
> ./vsock_perf --port <port> --rcvlowat <SO_RCVLOWAT>
>
> Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
> ---
> tools/testing/vsock/Makefile     |   3 +-
> tools/testing/vsock/README       |  34 +++
> tools/testing/vsock/vsock_perf.c | 441 +++++++++++++++++++++++++++++++
> 3 files changed, 477 insertions(+), 1 deletion(-)
> create mode 100644 tools/testing/vsock/vsock_perf.c
>
> diff --git a/tools/testing/vsock/Makefile b/tools/testing/vsock/Makefile
> index f8293c6910c9..43a254f0e14d 100644
> --- a/tools/testing/vsock/Makefile
> +++ b/tools/testing/vsock/Makefile
> @@ -1,8 +1,9 @@
> # SPDX-License-Identifier: GPL-2.0-only
> -all: test
> +all: test vsock_perf
> test: vsock_test vsock_diag_test
> vsock_test: vsock_test.o timeout.o control.o util.o
> vsock_diag_test: vsock_diag_test.o timeout.o control.o util.o
> +vsock_perf: vsock_perf.o
>
> CFLAGS += -g -O2 -Werror -Wall -I. -I../../include -I../../../usr/include -Wno-pointer-sign -fno-strict-overflow -fno-strict-aliasing -fno-common -MMD -U_FORTIFY_SOURCE -D_GNU_SOURCE
> .PHONY: all test clean
> diff --git a/tools/testing/vsock/README b/tools/testing/vsock/README
> index 4d5045e7d2c3..e6f6735bba05 100644
> --- a/tools/testing/vsock/README
> +++ b/tools/testing/vsock/README
> @@ -35,3 +35,37 @@ Invoke test binaries in both directions as follows:
>                        --control-port=$GUEST_IP \
>                        --control-port=1234 \
>                        --peer-cid=3
> +
> +vsock_perf utility
> +-------------------
> +'vsock_perf' is a simple tool to measure vsock performance. It works in
> +sender/receiver modes: sender connect to peer at the specified port and
> +starts data transmission to the receiver. After data processing is done,
> +it prints several metrics(see below).
> +
> +Usage:
> +# run as sender
> +# connect to CID 2, port 1234, send 1G of data, tx buf size is 1M
> +./vsock_perf --sender 2 --port 1234 --bytes 1G --buf-size 1M
> +
> +Output:
> +tx performance: A Gb/s
> +
> +Output explanation:
> +A is calculated as "number of bytes to send" / "time in tx loop"
> +
> +# run as receiver
> +# listen port 1234, rx buf size is 1M, socket buf size is 1G, SO_RCVLOWAT is 64K
> +./vsock_perf --port 1234 --buf-size 1M --vsk-size 1G --rcvlowat 64K
> +
> +Output:
> +rx performance: A Gb/s
> +total in 'read()': B sec
> +POLLIN wakeups: C
> +average in 'read()': D ns
> +
> +Output explanation:
> +A is calculated as "number of received bytes" / "time in rx loop".
> +B is time, spent in 'read()' system call(excluding 'poll()')
> +C is number of 'poll()' wake ups with POLLIN bit set.
> +D is B / C, e.g. average amount of time, spent in single 'read()'.

Since now we prints Gbits/s I think we should update the previous lines.
But the rest looks good to me. So with the updated README:

Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>

Thanks,
Stefano