Slow disk write speeds over network

Eric Anderson anderson at
Mon Jun 9 15:16:39 PDT 2003

Chuck Swiger wrote:
> 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.

I see it in both NFS and ftp transfers, but like I said in one of my 
other notes, I have 4 network cards in this machine, all act the same way.

> 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?

Yes - and I just tried that suggestion - same thing.  No help. 
Interfaces look ok.


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

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