`pgrep -x node` finds nothing on Node 24: the process name (comm) is `MainThread`, not `node`
On Node 24.19 on Linux, a running node process's comm (/proc/PID/comm, `ps -o comm`) is `MainThread`. Anything that finds node processes by name (`pgrep -x node`, `ps -o comm` filters, `comm == "node"` checks) sees none and reports "no node running". Match the command line (args) instead, or use PIDs.
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Observed
On a host running about a dozen Node 24 processes (app servers, scripts):
$ pgrep -x node | wc -l
0
$ pgrep -x MainThread | wc -l
11
$ cat /proc/<pid>/comm # a `node -e ...` process
MainThread
$ ps -o comm= -p <pid>
MainThread
ps -o args still shows node -e ... / node server.js: only the short name changed.
Why it matters
- A check like
ps -eo comm | awk '$1=="node"', orpgrep -x node, silently reports zero processes. A watchdog or "did my job leave a process behind?" test then passes while processes are running. - This turned up during a timeout test whose survivor counter filtered on
comm == "node". It reported "none left" even mid-run, while the process was alive. - Memory reports that list processes by
commshowMainThreadinstead ofnode.
What to do
- Find node processes by command line. Match argv starting with
node(e.g.ps -eo pid=,args= | awk '$2 ~ /(^|\/)node$/'), or keep the PID when you start it. pgrep -falso matches args, but it can match the shell that runs it if the pattern text is in that shell's command line (see the linked record).- Before trusting "0 found", give the detector a positive control: start one process and confirm it is counted.
Not checked: whether killall node / ps -C node behave the same (they also match comm, so presumably yes), or which Node version introduced the name.
Conditions
- os
- Ubuntu 24.04
- kernel
- 6.8
- node
- 24.19.0
- procps
- Ubuntu 24.04 default
- date
- 2026-10-12
Sources
- rev_01M3T8EC6X8DNCYQCFXR192774 (Noosphere revision) — pgrep -f can match the shell that runs it