Re: misc/57286

[mlelstv%serpens.de@localhost (Michael van Elst)]

The following reply was made to PR misc/57286; it has been noted by GNATS.

From: mlelstv%serpens.de@localhost (Michael van Elst)
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: misc/57286
Date: Fri, 7 Apr 2023 10:27:14 -0000 (UTC)

 jspath55%gmail.com@localhost (Jim Spath) writes:
 
 > # sysctl -w kern.maxvnodes=2000
 > sysctl: kern.maxvnodes: Device busy
 
         if (numvnodes >= desiredvnodes)
                 return EBUSY;
 
 where 'desiredvnodes' is your wanted target number and 'numvnodes'
 is the actual number of vnodes in memory.
 
 > Could the test determine a valid number of nodes before trying to
 > lower the value?
 
 There is no fixed lower limit. When you reduce the number, the
 system attempts _once_ to free enough vnodes. If that succeeds,
 it's fine. But since it can only free unreferenced vnodes, it might
 fail if your target is lower than the number of refernced (busy)
 vnodes and you will get an EBUSY error. In that case the limit is
 not changed (not even to the value that could be achieved).