NFSD process amount

Dear all,

I've got a NFS clustered service with NFSDCOUNT set to 75.
This process number is being monitored and we've found that each night around 4:30am, one more process appears and then disappears. Nothing specific is being shown on system logs

We have no specific crontab job at this time except default logrotate.
I've suspected this could be due to the SIGHUP of logrotate but could not reproduce on my lab. Anyway, SIGHUP should not fork a new child process...

Does anyone would have an idea?
(please note that I cannot disable logrotate on our production cluster as a matter of test)

Thank you,

Antoine