Commit 0ea89560 authored by Michal Berger's avatar Michal Berger Committed by Tomasz Zawadzki
Browse files

test/scheduler: Add function for calculating cpu load 



This is done in order to detect cpu times in a more deterministic
fashion.

Signed-off-by: default avatarMichal Berger <michalx.berger@intel.com>
Change-Id: I005d6fececdc15500bcf637e96f2fbecbd4273f1
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/7563


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Reviewed-by: default avatarTomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
parent 413808e1

test/scheduler/common.sh

+93 −3
Original line number Diff line number Diff line
@@ -370,14 +370,15 @@ _get_thread_stats() { 


get_cpu_stat() {

	local cpu_idx=$1

	local stat=$2 stats

	local stat=$2 stats astats



	while read -r cpu stats; do

		[[ $cpu == "cpu$cpu_idx" ]] && stats=($stats)

		[[ $cpu == "cpu$cpu_idx" ]] && astats=($stats)

	done < /proc/stat



	case "$stat" in

		idle) echo "${stats[3]}" ;;

		idle) echo "${astats[3]}" ;;

		all) printf '%u\n' "${astats[@]}" ;;

		*) ;;

	esac

}
@@ -393,3 +394,92 @@ destroy_thread() { 
active_thread() {

	rpc_cmd --plugin "$plugin" scheduler_thread_set_active "$@"

}



get_cpu_time() {

	xtrace_disable



	local interval=$1 cpu_time=$2 interval_count

	shift 2

	local cpus=("$@") cpu

	local stats stat old_stats avg_load

	local total_sample



	# Exposed for the caller

	local -g cpu_times=()

	local -g avg_cpu_time=()



	# cpu_time:

	# 0 - user (time spent in user mode)

	# 1 - nice (Time spent in user mode with low priority)

	# 2 - system (Time spent in system mode)

	# 3 - idle (Time spent in the idle task)

	# 4 - iowait (Time waiting for I/O to complete)

	# 5 - irq (Time servicing interrupts)

	# 6 - softirq (Time servicing softirqs)

	# 7 - steal (Stolen time)

	# 8 - guest (Time spent running a virtual CPU)

	# 9 - guest_nice (Time spent running a niced guest)



	local -A cpu_time_map

	cpu_time_map["user"]=0

	cpu_time_map["nice"]=1

	cpu_time_map["system"]=2

	cpu_time_map["idle"]=3

	cpu_time_map["iowait"]=4

	cpu_time_map["irq"]=5

	cpu_time_map["softirq"]=6

	cpu_time_map["steal"]=7

	cpu_time_map["guest"]=8

	cpu_time_map["guest_nice"]=9



	# Clear up the env

	unset -v ${!stat_@}

	unset -v ${!old_stat_@}

	unset -v ${!avg_stat@}

	unset -v ${!avg_load@}



	cpu_time=${cpu_time_map["$cpu_time"]:-3}

	interval=$((interval <= 0 ? 1 : interval))

	# We skip first sample to have min 2 for stat comparision

	interval=$((interval + 1)) interval_count=0

	while ((interval_count++, --interval >= 0)); do

		for cpu in "${cpus[@]}"; do

			local -n old_stats=old_stats_$cpu

			local -n avg_load=avg_load_$cpu

			sample_stats=() total_sample=0



			stats=($(get_cpu_stat "$cpu" all))

			if ((interval_count == 1)); then

				# Skip first sample

				old_stats=("${stats[@]}")

				continue

			fi

			for stat in "${!stats[@]}"; do

				avg_load[stat]="stat_${stat}_${cpu}[@]"

				sample_stats[stat]=$((stats[stat] - old_stats[stat]))

				: $((total_sample += sample_stats[stat]))

			done

			for stat in "${!stats[@]}"; do

				local -n avg_stat=stat_${stat}_${cpu}

				avg_stat+=($((sample_stats[stat] * 100 / (total_sample == 0 ? 1 : total_sample))))

			done

			old_stats=("${stats[@]}")

		done

		sleep 1s

	done



	# We collected % for each time. Now determine the avg % for requested time.

	local load stat_load

	for cpu in "${cpus[@]}"; do

		load=0

		local -n avg_load_cpu=avg_load_$cpu

		stat_load=("${!avg_load_cpu[cpu_time]}")

		for stat in "${stat_load[@]}"; do

			: $((load += stat))

		done

		cpu_times[cpu]=${stat_load[*]}

		avg_cpu_time[cpu]=$((load / ${#stat_load[@]}))

	done



	xtrace_restore

}