Subject: Re: Consistent vnlock dead locks in low memory conditions
To: Manuel Bouyer <>
From: Stephen Jones <>
List: tech-net
Date: 06/22/2006 14:57:30
On Jun 22, 2006, at 2:15 PM, Manuel Bouyer wrote:
> Depends on RAM available, and other things I guess
>> Would that really cause a deadlock?
> in my experience, yes.

What sort of 'other things' and can you please tell me more about  
your experiences?
> If you didn't change the default value then it's probably OK.

They usually all show up as allocated in systat within a few hours of  
system running no matter what the setting is set to.  Is that  
probably OK too?

>> BUFCACHE I have set to 6 (%) in the kernel, can that be set
>> via sysctl as well?
> Yes, it's vm.bufcache.

What I really meant to ask is it dynamic though?  Can it only be  
increased without a reboot
or drop to single user mode?

> If it's a NFS server it doens't matter; this is for clients.

This particular server is an NFS client as well.  I typically see  
vnlock deadlocks
on clients and rarely on a server.  However, this case is a bit of  
exception as it only
has one served file system and its nfsd are the first to deadlock.