I think the first step is to get the ability to tune clients, and then experimentally determine how to optimally tune clients.
That's where the BFI method comes in. I know from long experience running mail servers that you can often speed up throughput by reducing sessions. Your "one fast upload" scenario has one saving grace: it's fast, it's going fast, it won't last long -- the faster it goes, the sooner it is gone. As long as we're operating at a reasonable load, that is -- different story when we're overloaded by an order of magnitude. -- Lynn Martin wrote: > Martin wrote: > [...] >> OK, to guess some numbers... >> >> Uploads: >> >> s...@h has a 100Mb/s pinch point on their link; >> >> A typical UK (adsl) uplink is anything from 128kb/s up to 1Mb/s >> depending on the connection. Most I guess will be 512kb/s or 768kb/s. >> Add in a few dial-up 8kb/s, and then hope that there are no academic >> links that can blast out a full 100Mb/s... >> >> That means that for a "guestimate", you don't want more than about 150 >> to 200 simultaneous uploads. Note also that just one fast upload can >> skittle the lot into link saturation. >> >> >> Can the Boinc servers monitor the incoming uploads and simply defer or >> deny new upload requests until the incoming data rate is seen to drop >> below 80% of link capacity. >> >> *That has just got to be a simple fix* ! > > Note also that the same goes for *downloads* from the project servers. > > Taking the example of s...@h and typical speeds for the UK, that suggests > that you do not want more than just *20* simultaneous downloads to avoid > disgracefully saturating your link. > > And again, just one fast download can skittle everyone into lost data > and multiple tcp retries. > > Defer new download requests until link utilisation is seen to be <80% > oncemore? > > > Regards, > Martin > > _______________________________________________ boinc_dev mailing list [email protected] http://lists.ssl.berkeley.edu/mailman/listinfo/boinc_dev To unsubscribe, visit the above URL and (near bottom of page) enter your email address.
