[freenet-dev] [freenet-cvs] r11679 - in trunk/apps/load-balancing-sims/phase7/sim: . clients messages

[Matthew Toseland]

On Thu, Feb 08, 2007 at 10:44:41PM +0000, Michael Rogers wrote:
> 
> > 52 = 5% * 1000. The probability of a packet being dropped is less than
> > 5% on most useful links.
> 
> Sorry, I don't see how the loss rate of the link is relevant - I'm 
> talking about the overhead of sending an ack straight away (52 bytes) 
> versus the overhead of retransmitting a packet unnecessarily (1000 
> bytes). Unnecessary retransmissions happen when the RTT variance is 
> high, which it is at the moment because acks are held for anywhere 
> between 0 and 100ms. Currently we retransmit a packet if it hasn't been 
> acked for 4 * RTT + MAX_DELAY, but we don't know what fraction of acks 
> arrive after 4 * RTT + MAX_DELAY. If it's more than 5% then it would be 
> cheaper to send the acks straight away.

Simulations maybe?

Most packets are less than 1000 bytes in practice.

What exactly does TCP do? I thought it combined ack's with data in order
to minimize overhead.
> 
> Cheers,
> Michael
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