Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 28 Jun 1996 16:08:44 +0200 (MET DST)
From:      Juergen Lock <nox@jelal.hb.north.de>
To:        davidg@root.com
Cc:        jhay@mikom.csir.co.za, stable@FreeBSD.org
Subject:   Re: lockups.
Message-ID:  <199606281408.QAA01040@saturn.hb.north.de>
In-Reply-To: <199606270232.TAA00264@root.com> from David Greenman at "Jun 26, 96 07:32:14 pm"

next in thread | previous in thread | raw e-mail | index | archive | help
David Greenman writes:

>    Yes, this does help. I've also discovered the true nature of the problem in
> the meantime - swapping was broken. Basically, the pmap layer always returns
> "TRUE" for the upages (kernel stack and u area) and while swapout() made the
> pages pageable, they were never completely removed from the address space. The
> result was that the pages could never be made clean and would be continually
> paged out. This caused the pagedaemon to loop endlessly in some cases while
> memory remained in short supply. The problem isn't noticed when the RSS
> limiting code is enabled because it (apparantly) has the side effect of
> more forcefully removing the process pages and thus side-steps the problem.
>[...]

Update:  i'm running vm_glue.c 1.20.4.6 + vm_pageout.c 1.51.4.11 now,
and performance is at least :) as good again as it was.
problem solved.  (apparently, unless there are new bugs...)

 oh and ipfw, this is what i now do for the first rule

#! /bin/sh
ipfw f

if /sbin/ipfw add 8500 accept icmp from any to any; then
        x=/sbin/ipfw
else
        # kernel older than 0696...
        x=/sbin/ipfw-2159
        $x add 8500 accept icmp from any to any
fi

 (ipfw-2159 is the old ipfw) and then use $x for ipfw in the rest
of the script.

 just in case anyone else here sometimes boots older kernels...
or makes mistakes while updating remote :)
	Juergen



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199606281408.QAA01040>