Slow disk write speeds over network

Eric Anderson anderson at centtech.com
Mon Jun 9 12:34:52 PDT 2003


Ok, I have a file server (NFS) running FreeBSD 4.8-RC1, which is having 
incredibly slow disk write speeds.  Locally, doing something like:
dd if=/dev/zero of=/partition/testfile
Shows 14MB/s - which is what I expect..

However, ftping a file or cp'ing over NFS shows speeds less than 1MB/s - 
which is not what I would expect - it's got gigabit ethernet, and has 
very fast read times (via ftp or nfs) over the network.

After looking around, I noticed (when doing a systat -vmstat), that the 
vnode information looked a little strange.. like so:

54120 desiredvnodes
49163 numvnodes
35903 freevnodes

Shouldn't I have a higher "numvnodes" than "desiredvnodes"?

What else am I missing here?  I have built many FreeBSD NFS file 
servers, and this is the first time I've had a slow one.  I suspect 
maybe a sysctl tweak I bumped upon building the machine, or possibly 
something I didn't tweak.

Any hints?

Eric


-- 
------------------------------------------------------------------
Eric Anderson	   Systems Administrator      Centaur Technology
Attitudes are contagious, is yours worth catching?
------------------------------------------------------------------



More information about the freebsd-performance mailing list