Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 9 Feb 2003 17:48:25 -0600
From:      Dan Nelson <dnelson@allantgroup.com>
To:        Tillman <tillman@seekingfire.com>
Cc:        freebsd-questions@FreeBSD.ORG
Subject:   Re: speeding up NFS
Message-ID:  <20030209234825.GJ5356@dan.emsphone.com>
In-Reply-To: <20030209174109.B32740@seekingfire.com>
References:  <200302091717.42138.ajacoutot@lphp.org> <20030209192839.GH5356@dan.emsphone.com> <20030209174109.B32740@seekingfire.com>

next in thread | previous in thread | raw e-mail | index | archive | help
In the last episode (Feb 09), Tillman said:
> Which sysctl is this? The closest I can find is:
> 
> # sysctl -a | grep nfs | grep sync
> vfs.nfs.async: 0

Same one.  They split the server sysctls out into nfsrv in 5.*.  
 
> If that's the one, it may still not be necessary. I'm getting about
> 8.5-9 Megabytes/s on NFS reads from a Linux 2.4 client (on a 100Mbit
> switched LAN) with it set to 0, as measured by Bonnie++. This is
> fairly close to the 12MB/s fast ethernet theoretical maximum, so I'm
> happy with performance.

It only applies to writes.  With it set to 0 (the default), FreeBSD
follows the NFS spec and does not return from NFSv2 write or NFSv3
commit calls without having synced the data to disk.  This can slow you
down if you are not on a battery-backed RAID or ramdisk.  With NFSv3
it's not so bad since it supports async client writes (i.e. separate
write and commit calls).

-- 
	Dan Nelson
	dnelson@allantgroup.com

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20030209234825.GJ5356>