docs/125587: FAQ entry 5.13 -- adjustion is not an English word; tunable?

[Wayne Sierke]

The following reply was made to PR docs/125587; it has been noted by GNATS.

From: Wayne Sierke <ws at au.dyndns.ws>
To: Mike Small <smallm at panix.com>
Cc: bug-followup at freebsd.org
Subject: Re: docs/125587: FAQ entry 5.13 -- adjustion is not an English
	word; tunable?
Date: Mon, 14 Jul 2008 15:05:22 +0930

 On Mon, 2008-07-14 at 03:16 +0000, Mike Small wrote:
 > Secondly, the same paragraph also uses the word "tunable" as a noun.
 > Is this a term people use in BSD?  I mean, it's clear what's meant
 > from the context, but using "variable" or "sysctl variable", as is
 > done in the first paragraph, seems clearer and less strange to me.
 
 My understanding is that the term 'tunable' is used to refer to sysctl
 variables that can only be set at boot - i.e. are read-only at run-time.
 
 
 How about this?:
 
 The FreeBSD kernel limits the number of processes that may exist at one
 time. The default limit is based on the kern.maxusers sysctl(8)
 variable. kern.maxusers also affects various other in-kernel limits,
 such as network buffers (see this earlier question). If your machine is
 heavily loaded, you probably want to increase kern.maxusers. This will
 increase these other system limits in addition to the maximum number of
 processes.
 
 To adjust the kern.maxusers value, see the File/Process Limits section
 of the Handbook. (While that section refers to open files, the same
 limits apply to processes.)
 
 If your machine is lightly loaded and you are simply running a very
 large number of processes, you can adjust this with the kern.maxproc
 tunable. The value of this sysctl ´variable¡ is set at boot time and can
 only be changed by placing an appropriate entry in /boot/loader.conf and
 rebooting.
 
 If a large number of processes need to be run by a single user,
 kern.maxprocperuid should also be modified. Its maximum value should be
 one less than the kern.maxproc value because one system program,
 init(8), must always be running. For more information about setting
 tunables see the loader.conf(5) manual page.
 
 To make a sysctl change permanent place the proper value
 in /etc/sysctl.conf. More information about system tuning with sysctl(8)
 can be found at the Tuning with sysctl section of the Handbook.
 
 
 
 I'm not sure about the veracity of the "kern.maxprocperuid should be one
 less than kern.maxproc" statement. Does anyone know about this?