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Re: [Nbd] Performance tuning of nbd !?


> > When I try it over cable (okay, might be a little bit perverted - 25Mbit/s 
> > ping of 15ms) or DSL (14Mbit/s ping of 35ms) the results drop to less than 
> > 200kByte/sek. It is still possible to run a stateless client that way 
> > (squashfs ontop of nbd), but you have to be patient while an app is 
> > starting the first time.
> > Is there any chance to get above the 10Mbit/s LAN rate in the WAN DSL or 
> > cable scenarios!?
> Yes. I think you should be able to use about 70% of the bandwidth (I can get
> about 32Mb/s out of 45Mb/s (T3) with 100ms latency). You might need to
> increase your TCP window size and/or change the I/O scheduler you're using
> for NBD. Switch to "deadline" scheduler if you're not using that one already.
> And set the TCP window size, as follows:

Checked my setup: Somebody told me a while ago that read ahead isn't of any use
for networked setups ... I changed the value from 0 to the original and the
speed got up significantly. Now I'm getting the 1000kB/s expected by your
description :) But the boot time over the net with the new settings did not
increase by a significant factor ...

Ciao, Dirk

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