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Re: apt and multiple connections

Jason Gunthorpe wrote:
> On Sat, 23 Sep 2000, Glenn McGrath wrote:
> > It would mean that the load placed on mirrors would be distributed a lot
> > better, so it would be good for clients and servers, a win-win
> > situation.
> Erm.. If the client uses more bandwidth, where does that bandwidth come
> from? It isn't created out of nothing.

No, the client can optimally use as much bandwidth as is available, if a
client goes via a 56kbit/s modem, then it is very unlikely that an
offical debian mirror wouldnt be unable to saturate that connection, say
for whatever reason that the server being used could only supply 3 KB/s,
then the client still has 2KB/s of available bandwidth that isnt being
used. This 2KB/s could be supplied by a different mirror to download the
same file.

The way it is now that extra 2KB/s could used by apt to download a
different file from another server, it is just a natural progression to
enable it to use all of its bandwidth to download any 1 deb.

Obviously the benefits of threaded gets is dependent on the clients
bandwidth, the more bandwidth a client has the greater the benefit.

> If the client uses multiple hosts
> to increase their traffic then more bandwidth is eaten from those hosts
> that would not have been otherwise.
I think we must be mis-understanding each other.

The bandwidth being supplied by any number of servers to any 1 client
will never be more than that clients bandwidth.
If a client uses 1/3 of its bandwidth on each of 3 servers it eats no
more bandwidth from the collective servers than if it downloaded from
only 1 at full speed. 

> Our load balancing on mirrors is actually pretty darn even according to my
> stats, so I'm not too worried about that.
> Jason

Yea, fair enough, a distributed debian mirror would still be cool i
think, debian has great support for its mirrors, but a distributed
mirror would have advantages in that it would make debian less dependent
on centralised institutional servers. A distributed debian mirror
couldnt happen (practicly) without threaded gets.


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