On Friday 31 October 2003 19:03, Toad wrote: > On Fri, Oct 31, 2003 at 04:52:42PM +0000, Richard Lamont wrote:
> > Following the recent improvements, pSuccessRatio seems to have > > moved from around 2% to around 2.5% and stayed there. > > Unfortunately psuccess doesn't seem to actually mean anything. And it > won't, at least not until we get the stats sorted out - probably by > implementing the SFT... Well, if the stats are telling porkies, diagnosing the problem is even more difficult. > > The objective is to get keys from a node that has them to the node > > that wants them. Freenet needs designing to maximise the speed of > > delivery of keys. > > > > If messages take up none of the bandwidth, then no requests could > > be made, and no keys would get delivered. > > > > If messages take up all of the bandwidth, then there would be no > > bandwidth left for keys, and no keys would get delivered. > > > > Somewhere between these two extremes, there must be an optimum > > split of bandwidth between keys and messsages that maximises the > > rate at which keys are delivered. > > What would you suggest? Giving trailers a higher priority will only > drive up messageSendTimeRequest and make the node useless. Is it a > routing problem? Is it that 95% of requests are for data that simply > isn't on the network? In which case, we need to look at enlarging the > failure table - 1000 keys is simply too small for current usage > IMNSHO. The usefulness of a node is a function of its ability to deliver keys. All I'm suggesting is that if the bandwidth is allocated 80:20 keys:messages then Freenet will be four times as fast than if the ratio is the other way round (as it appears to be at present). As for which messages are dropped or delayed, I couldn't comment. I don't know enough about it, and AFAIK FNP isn't documented so it's more or less impossible to learn how it works. All I'm saying is that if 80% of the bandwidth is spent shifting keys, then Freenet will go four times as fast as at present. > > The ideal rate of sending messages would be the rate which is just > > enough to keep keys flowing fast enough to fill the pipe. Any more > > is worse than useless, because it will just waste bandwidth. > > Why is "wasting bandwidth" such a big deal? I can't believe you are asking this question. Most Freenet users are on cable modem or ADSL connections, with typically a 128 or 256 kbit/sec uplink. The default config bwlimits to 12000 Bytes/sec. If 80% of that is spent on message overhead, then payload can only move out of a node at a paltry 2400 bytes/sec. And even that is shared between all the TXing connections. Bandwidth is the most precious and scarce resource that Freenet uses. Everything else - e.g. CPU and disk - is plentiful and cheap by comparison. So to optimise Freenet's performance, it is essential to use Bandwidth economically. Surely I can't be the first one to point out something as basic and obvious as this? > > Have the developers given this any thought? All I've seen are one > > or two hints in various places that messages must have priority > > over payload. If developers are working on the basis of this > > belief, then that is the root of the performance problem. > > I repeat my question. There are lots of packets mainly because > routing doesn't usually find the node we want the first time, and > because a lot of queries fail, many of which are for data that wasn't > there in the first place. Messages must have priority over trailers > in order to be delivered in reasonable time - or that's the current > understanding anyway. QueryRejected messages and so on have a lower > priority though. But the basic misunderstanding here: we create > messages for a reason, we don't just pluck them out of thin air... Please step back from all this detail and look at the big picture. You create messages for a reason: to obtain keys. Keys can only flow at a certain rate, limited by bandwidth. There's no point in sending any more messages than just enough to get those keys sent, because they cannot achieve anything. As for which messages to throw away, I don't know enough about FNP's innards to offer any useful suggestion, and I'm more than happy to leave that to you. I'm reminded of an old cartoon I saw years ago. It showed a huge open plan office with hundreds of men in suits sat at desks punching calculators. At the back the back of the room, there were two men watching this scene. One of them, the boss, says to the other, "Do you know, Jenkins, no matter how many accountants I employ, I can't seem to find out where all the money is going." Freenet is a bit like that. It spends too much of the firm's money on accountants. -- Richard Lamont <[EMAIL PROTECTED]> OpenPGP Key ID: 5ABEC9C3 http://www.stonix.demon.co.uk/key.txt Fingerprint: 9DEE 7113 DF02 A516 404C 22AC 1FF6 185D 5ABE C9C3 _______________________________________________ Devl mailing list [EMAIL PROTECTED] http://dodo.freenetproject.org/cgi-bin/mailman/listinfo/devl
