chore(tools): measure bench CPU time from schedstat

commit: 6d0032ffa888061d058b322a36154a5d7c810f58
author: brice · 9d ago · 2026-10-13 16:06 UTC
parent: 99ddc5d
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

1 file · +6 -6

M tools/bench/bench.sh +6 -6


@@ -58,20 +58,20 @@ pids+=("$!")
58	58		sleep 8
59	59
60	60		cs() { cat /proc/"$nwl"/task/*/status \| awk '/^voluntary_ctxt/{v+=$2} END{print v}'; }
61		-	ticks() { awk '{print $14+$15}' /proc/"$nwl"/stat; }
	61	+	# CPU time in ns summed over threads (schedstat is finer than stat's ticks).
	62	+	ticks() { cat /proc/"$nwl"/task/*/schedstat \| awk '{v+=$1} END{printf "%d\n", v}'; }
62	63		frames() { grep -c '"message":"frame"' "$log" \|\| true; }
63	64
64	65		t0=$(ticks); f0=$(frames); c0=$(cs)
65	66		sleep "$secs"
66	67		t1=$(ticks); f1=$(frames); c1=$(cs)
67	68
68		-	hz=$(getconf CLK_TCK)
69		-	python3 - "$((t1 - t0))" "$((f1 - f0))" "$((c1 - c0))" "$secs" "$hz" "$page" <<'EOF'
	69	+	python3 - "$((t1 - t0))" "$((f1 - f0))" "$((c1 - c0))" "$secs" "$page" <<'EOF'
70	70		import sys
71		-	t, f, c, s, hz, page = int(sys.argv[1]), int(sys.argv[2]), int(sys.argv[3]), float(sys.argv[4]), int(sys.argv[5]), sys.argv[6]
72		-	cpu = t / hz / s * 100
	71	+	t, f, c, s, page = int(sys.argv[1]), int(sys.argv[2]), int(sys.argv[3]), float(sys.argv[4]), sys.argv[5]
	72	+	cpu = t / 1e9 / s * 100
73	73		fr = max(f, 1)
74		-	print(f"{page} cpu%={cpu:.2f} fps={f / s:.1f} ms/frame={t / hz * 1000 / fr:.3f} cs/frame={c / fr:.0f}")
	74	+	print(f"{page} cpu%={cpu:.2f} fps={f / s:.1f} ms/frame={t / 1e6 / fr:.3f} cs/frame={c / fr:.0f}")
75	75		EOF
76	76
77	77		if [ -n "${BENCH_KEEP:-}" ]; then

 sleep 8
 cs() { cat /proc/"$nwl"/task/*/status | awk '/^voluntary_ctxt/{v+=$2} END{print v}'; }
-ticks() { awk '{print $14+$15}' /proc/"$nwl"/stat; }
+# CPU time in ns summed over threads (schedstat is finer than stat's ticks).
+ticks() { cat /proc/"$nwl"/task/*/schedstat | awk '{v+=$1} END{printf "%d\n", v}'; }
 frames() { grep -c '"message":"frame"' "$log" || true; }
 t0=$(ticks); f0=$(frames); c0=$(cs)
 sleep "$secs"
 t1=$(ticks); f1=$(frames); c1=$(cs)
-hz=$(getconf CLK_TCK)
+python3 - "$((t1 - t0))" "$((f1 - f0))" "$((c1 - c0))" "$secs" "$page" <<'EOF'
-python3 - "$((t1 - t0))" "$((f1 - f0))" "$((c1 - c0))" "$secs" "$hz" "$page" <<'EOF'
 import sys
-t, f, c, s, hz, page = int(sys.argv[1]), int(sys.argv[2]), int(sys.argv[3]), float(sys.argv[4]), int(sys.argv[5]), sys.argv[6]
+t, f, c, s, page = int(sys.argv[1]), int(sys.argv[2]), int(sys.argv[3]), float(sys.argv[4]), sys.argv[5]
-cpu = t / hz / s * 100
+cpu = t / 1e9 / s * 100
 fr = max(f, 1)
-print(f"{page} cpu%={cpu:.2f} fps={f / s:.1f} ms/frame={t / hz * 1000 / fr:.3f} cs/frame={c / fr:.0f}")
+print(f"{page} cpu%={cpu:.2f} fps={f / s:.1f} ms/frame={t / 1e6 / fr:.3f} cs/frame={c / fr:.0f}")
 EOF
 if [ -n "${BENCH_KEEP:-}" ]; then