benchmarking: correct for differences in CPU and TSC frequency

1 files changed, 14 insertions, 0 deletions

diff --git a/etc/cpufreq b/etc/cpufreq
new file mode 100755
index 000000000..bc5a66a85
--- /dev/null
+++ b/etc/cpufreq
@@ -0,0 +1,14 @@
+#!/bin/sh
+set -eu
+
+for cpu in $(seq 1 $(nproc)); do
+	echo "scale=100000;pi=4*a(1);0" | bc -l &
+	echo $!
+done | ( \
+	sleep .1 ;
+        mhz=$(cat /proc/cpuinfo | grep "^[c]pu MHz" | cut -d: -f2 | tr -d ' ' | sort -nr | head -1);
+	printf "$(echo "scale=2; ($mhz + 5)/1000" | bc)\n"
+        while IFS= read -r pid; do
+		kill "$pid";
+	done )
+