scripts/perf: Add tool for collecting vmstat

#!/usr/bin/env bash

#  SPDX-License-Identifier: BSD-3-Clause

#  Copyright (C) 2023 Intel Corporation

#  All rights reserved.

shopt -s nullglob extglob

pmdir=$(readlink -f "$(dirname "$0")")

rootdir=$(readlink -f "$pmdir/../../../")

help() {

	cat <<- HELP

		Usage: $0 [-h] [-c count] [-d dir] [-p prefix] [-r reprint_header_count]

		-h - Print this message.

		-c - Execute count times. 0 is the default and it means to run

		     indefinitely.

		-d - Directory where results should be saved. Default is /tmp.

		-p - Add prefix to saved files.

		-r - Stat count after which header should be re-printed. Default is 20.

		-t - How long to wait before each stat dump. Default is 1s.

		When started, ${0##*/} will enter loop to continuosly dump

		vmstat. Each iteration will be logged to stderr and a log file

		(dir/${0##*/}.pm.log).

	HELP

}

get_extra_meminfo() {

	local match="" data

	match+="|MemAvailable"

	match+="|Shmem"

	match+="|HugePages_(Total|Free)"

	match+="|Hugepagesize"

	data=($(grep -E "^($match):" /proc/meminfo | awk '{print $2}'))

	echo "${data[*]}"

}

_vmstat() {

	local count=$1 interval=$2 reprint_header=${3:-20} _count

	local vmstat _vmstat stat_idx header=()

	_count=$count

	while ((stat_idx = stat_idx == reprint_header ? 1 : ++stat_idx, count <= 0 ? 1 : _count--)); do

		mapfile -t vmstat < <(vmstat --timestamp)

		# Enhance output to include stuff we are most interested in

		vmstat[2]="${vmstat[2]} $(get_extra_meminfo)"

		if ((stat_idx == 1)); then

			header=("${vmstat[@]::2}")

			header[0]="${header[0]}     ----extra memory----"

			# Keep the header ordered as in get_extra_meminfo()

			header[1]="${header[1]}     avail shmem hp_total hp_free hp_size"

			_vmstat=("${header[@]}" "${vmstat[2]}")

		else

			_vmstat=("${vmstat[2]}")

		fi

		printf '%s\n' "${_vmstat[@]}"

		sleep "${interval}s"

	done > >(tee "$output_dir/$log_file")

}

count=0

interval=1

output_dir=/tmp

prefix=""

reprint_header=20

while getopts c:d:hp:r:t: opt; do

	case "$opt" in

		c) count=$OPTARG ;;

		d) output_dir=$OPTARG ;;

		h)

			help

			exit 0

			;;

		p) prefix=$OPTARG ;;

		r) reprint_header=$OPTARG ;;

		t) interval=$OPTARG ;;

		*) ;;

	esac

done

declare -r log_file=${prefix:+${prefix}_}${0##*/}.pm.log

mkdir -p "$output_dir"

_vmstat "$count" "$interval" "$reprint_header"