NFS and kernel cache

[Mogens Kjaer]

Chris Adams wrote:
> I'm copying a big chunk of data to a single file on an NFS server (in
> this case, using ntfsclone to back up a NTFS partition).  Both the
> client and the server are on gigabit ethernet, and both are running FC6.
> 
> I see the disk LED come on solid for several seconds, then start
> flickering, then go out for a second or two.  If I watch the network
> switch, it does the opposite: no traffic, then a burst of traffic.
> Because of this, my total throughput is only about 200Mb/s.

Have you tested your network with ttcp?

When I want to move data fast from one machine to another,
it use ttcp as well:

On the receiver I start:

cd /some/place
ttcp -l10240 -r | tar xv -

Then on the transmitter:

cd /some/place
tar cf - . | ttcp -l10240 -t receiver

The number 10240 is the tar block size, 20x512

Mogens
-- 
Mogens Kjaer, Carlsberg A/S, Computer Department
Gamle Carlsberg Vej 10, DK-2500 Valby, Denmark
Phone: +45 33 27 53 25, Fax: +45 33 27 47 08
Email: mk at crc.dk Homepage: http://www.crc.dk