[no subject]

el@webmail.exetel.com.au>    <201003202324.o2KNOrlX006114@apollo.backplane.com> <1427.220.233.36.106.1269131275.squirrel@webmail.exetel.com.au>
From: Chris Turner <c.turner@199technologies.org>
Subject: Re: Machine unresponsive with cache_lock: blocked on... message
Date: Sun, 21 Mar 2010 18:56:26 +0000
BestServHost: crater.dragonflybsd.org
List-Post: <mailto:bugs@crater.dragonflybsd.org>
List-Subscribe: <mailto:bugs-request@crater.dragonflybsd.org?body=subscribe>
List-Unsubscribe: <mailto:bugs-request@crater.dragonflybsd.org?body=unsubscribe>
List-Help: <mailto:bugs-request@crater.dragonflybsd.org?body=help>
List-Owner: <mailto:owner-bugs@crater.dragonflybsd.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
In-Reply-To: <1427.220.233.36.106.1269131275.squirrel@webmail.exetel.com.au>
Sender: bugs-errors@crater.dragonflybsd.org
Errors-To: bugs-errors@crater.dragonflybsd.org
Lines: 21
NNTP-Posting-Host: 216.240.41.25
X-Trace: 1269197759 crater_reader.dragonflybsd.org 55376 216.240.41.25
Xref: crater_reader.dragonflybsd.org dragonfly.bugs:11550

elekktretterr@exemail.com.au wrote:
> question: why is HAMMER using so much memory, causing applications like
> postgres to use swap (and thus run slow).

this response isn't at all hammer related.. but in any case:

Still a bit fuzzy on some the related issues that might be at play here, 
but as I understand it, the postgres data cache uses as much shared 
memory as it 'wants' (e.g. up to max configured) to hold the database 
data - so if this machine was up for a long time, potentially the entire 
database data set is in memory -

and if the data set isn't used very often, it might get swapped out by 
something else running or just from inactivity ..

If you want to keep this from happening, you can set:

kern.ipc.shm_use_phys=1

in /boot/loader.conf