Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!ukc!strath-cs!baird!jim
From: jim@cs.strath.ac.uk (Jim Reid)
Newsgroups: comp.protocols.nfs
Subject: Re: how many nfsd's should I run?
Message-ID: <JIM.91Feb27110032@baird.cs.strath.ac.uk>
Date: 27 Feb 91 11:00:32 GMT
References: <28975@cs.yale.edu> <1991Feb24.025821.11354@news.iastate.edu>
	<thurlow.667370019@convex.convex.com>
Sender: jim@cs.strath.ac.uk
Organization: Computer Science Dept., Strathclyde Univ., Glasgow, Scotland.
Lines: 16
In-reply-to: thurlow@convex.com's message of 24 Feb 91 04:33:39 GMT

In article <thurlow.667370019@convex.convex.com> thurlow@convex.com (Robert Thurlow) writes:

   .........................  I was reminded of a reason to keep the
   numbers down that I had forgotten - SunOS will wake up all of the
   processes sleeping on the NFS input request socket, and the first
   one will get in.  That could be a lot of process jostling. 

This was certainly true for the early NFS implementations: say around
the time of SunOS2.0. Later implementations included a new kernel
function - wakeup_one() - which will only wake up one process waiting
on an event instead of every process waiting on that event. This is
intended to save the overheads of scheduling N nfsd processes only to
see N-1 of them immediately go back to sleep. The routine is still in
SunOS 4.[01].

		Jim