Closed ryanbowen closed 2 months ago
We can update the systemd configuration in https://github.com/Atoptool/atop/blob/master/atop.service to include:
LimitNOFILE=4096
Great debugging! Atop will automatically increase the number of allowed open files now to the limit which is needed for the current number of CPUs.
This solution is preferred above setting a fixed number in the atop.service
file which would introduce another (higher) limit again. Besides, this will not solve this issue for an interactive run.
This was a fun one to debug... it seems that atop has
2 * $CPUS + 30(ish)
open file descriptors when run as root. When running atop as service on high core count boxes this has the potential to put it over the default limit set by systemd of 1024 which causes it to not start.It tends to present as a failure to open
/proc/loadavg
which I'm guessing is the first place that a failed open is fatal:For reference, on this host it breaks:
On this one it's fine: