following-up to my own post: On Thursday,2009-09-24, at 0:00 , Zooko Wilcox-O'Hearn wrote:
> I'm leery of adding caching to Tahoe-LAFS proper because caching is > usually a tradeoff of gaining performance at a cost of correctness, > and the apps layered atop Tahoe-LAFS can know better than Tahoe- > LAFS can which of those tradeoffs are wins for them. Oh, and I should also mention because there is still a lot of "low hanging fruit" in improving Tahoe-LAFS performance without the complications introduced by caching mutable things. In fact, Tahoe-LAFS used to download files a lot faster -- about two *times* as fast over a 100 Mbps LAN, if I recall correctly -- and we made the segment size smaller in order to get better alacrity (i.e. for there to be a shorter delay between hitting "play" and the movie starting) and smoother download rate (to make Firefox 2 stop doing http://xkcd.com/612/ ). So, putting the segment size back to 1 MiB ought to make it much faster on upload on a fast network, right? Except if I recall correctly, it didn't make any difference over DSL when I tried it. Basically, there is probably something really dumb that we are doing which costs a large factor of upload/download speed in some cases, and as far as I know nobody has really analyzed network traces or otherwise figured out what the dumb thing is. I just created ticket #890 for the first step in diagnosing this. Regards, Zooko http://allmydata.org/trac/tahoe/ticket/809 # Measure how segment size affects upload/download speed. _______________________________________________ tahoe-dev mailing list [email protected] http://allmydata.org/cgi-bin/mailman/listinfo/tahoe-dev
