Subject: Re: [HACKERS] PostgreSQL, NetBSD and NFS
To: Ian Fry , Tom Lane <>
From: D'Arcy J.M. Cain <>
List: current-users
Date: 02/05/2003 15:01:27
On Wednesday 05 February 2003 13:04, Ian Fry wrote:
> > Wild thought here: can you reduce the MTU on the LAN linking the NFS
> > server to the NetBSD box?  If so, does it help?
> How about adjusting the read and write-size used by the NetBSD machine? I
> think the default is 32k for both read and write on i386 machines now.
> Perhaps try setting them back to 8k (it's the -r and -w flags to mount_nfs,

Hey!  That did it.  I hadn't tried that before because I had tried using the 
tcp option to mount and the docs suggested that that would do more than 
reducing the block size.  Besides, the man page didn't give the defaults and 
I was uncomfortable changing something when I didn't know from what.

So, why does this fix it?  It seems to me that it should have worked anyway.  
This feels rather fragile.  I doubt that it is hardware related because I dad 
tried it on the other ethernet interface in the machine which was on a 
completely different network than the one I am on now.

What is the implication of smaller read and write size?  Will I necessarily 
take a performance hit?

D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.