2026-03-12 20:23:15

tpt/tools/unix/runqlat.sh

@@ -0,0 +1,32 @@
+#!/bin/bash
+
+# Tiny Linux /proc/<pid>/schedstat demo script by Tanel Poder
+#   https://tanelpoder.com
+#
+# You may want to run this with high priority:
+#   sudo nice -n -10 ./runqlat.sh PID
+#
+# currently this script assumes that it will speep exactly for $SLEEP 
+# seconds, but it can itself be affected by CPU overload and you may 
+# see values that don't add up to 1000 ms per sec 
+# (or negative percentages in the derived BLKD% column)
+
+PID=$1
+SLEEP=1
+
+echo Sampling /proc/$PID/schedstat every $SLEEP seconds...
+
+printf "%6s %6s %6s\n" "CPU%" "RUNQ%" "SLP%"
+while true ; do
+    read -r CPU_NS_1 LAT_NS_1 SLICES_ON_THIS_CPU_1 < /proc/$PID/schedstat
+    sleep $SLEEP
+    read -r CPU_NS_2 LAT_NS_2 SLICES_ON_THIS_CPU_2 < /proc/$PID/schedstat
+
+    ON_CPU=$((($CPU_NS_2-$CPU_NS_1)/10000000)) 
+    ON_RUNQ=$((($LAT_NS_2-$LAT_NS_1)/10000000)) 
+    OTHER=$((100-($ON_CPU+ON_RUNQ)))
+
+    printf "%6d %6d %6d" $ON_CPU $ON_RUNQ $OTHER
+    echo
+done
+