Slow disk write speeds over network

Chuck Swiger cswiger at
Mon Jun 9 14:23:03 PDT 2003

Eric Anderson wrote:
> 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.

If the slowdown was only with regard to NFS, I'd ask you about what your NFS 
clients looked like.  However, if you're seeing a slowdown for FTP and other 
network protocols, it's more likely to be a physical problem with cabling, a NIC 
getting flaky, or something along those lines.

Do you have this connected to a managed switch so that you can take a look at 
the interface statistics for problems?  Maybe try cranking the NIC down from 
gigabit to 100Mbs ethernet speed and see whether that makes a difference?


More information about the freebsd-performance mailing list