[plug] NFS Large File writing causing "freezes"

[Craig Foster]

> -----Original Message-----
> From: plug-bounces at plug.org.au [mailto:plug-bounces at plug.org.au] On
> Behalf Of Tim
> Sent: Monday, 27 September 2010 7:41 AM
> To: plug at plug.org.au
> Subject: Re: [plug] NFS Large File writing causing "freezes"
> 
<snip>
> Other than a really small wsize, any other ideas for slowing
> down the transmit rate to something the NAS can handle? From watching
> the traffic graphs, it seems to ramp up the speed until it looses packets
> (>12MB/s) and then slows it down while retransmitting packets (to about
> 2MB/s) and then once the queues are cleared, it trys to ramp it back up again
> and the cycle continues.

So it works best at 100Mb speeds then? What about setting the NIC to a lower speed?

> Setting a small wsize (1024) means the transfer goes at a steady 2-3MB/s
> without long freezes or many RX errors.
> 
> I think I am realizing that if you want a decent NAS, building it yourself might
> not be such a bad idea. Having plenty of RAM and CPU would make things a
> lot better. (Although having a nas like the QNAP means it's quite, cool, and
> low power).
> 

FreeNAS makes it obscenely easy to do, and it supports iSCSI which is all sorts of awesome :)

> 
> Any ideas welcomed.
> 
> Thanks
> 
> Tim
> --

Craig F.