Hot thread live view

Live per-thread view; convert hot TID to hex (printf %x) to match jstack nid

top -H -p <pid>

More troubleshooting commands

Per-core CPU saturation

mpstat -P ALL 1

Per-core %usr/%sys/%iowait — spot a single saturated core vs balanced load
Run-queue vs cores

vmstat 1 5 | awk 'NR>2{print "runq="$1" blocked="$2}'; nproc

vmstat r column (runnable) above nproc means CPU saturation, not just high load
Process thread count

ps -o nlwp= -p <pid>; ps -eLf | wc -l

Thread count per pid and system-wide; runaway threads exhaust kernel.pid_max
RSS leak over time

while sleep 5; do ps -o rss= -p <pid> | awk '{print strftime("%T"),$1/1024"MB"}'; done

Sample RSS every 5s to confirm a real leak (monotonic growth) vs steady churn
Fast memory rollup

cat /proc/<pid>/smaps_rollup

One-shot Rss/Pss/Swap totals without parsing full smaps; cheap on huge maps