On Sat, 11 Jul 2009 11:22:51 -0700 Konstantin Svist <fry.kun@xxxxxxxxx> wrote: > gilpel@xxxxxxxxxx wrote: > > Why isn't this the default? > > > > > Probably because it doesn't work too well. > The way it works is by pinging the IPs of all mirrors to see which one > has the smallest latency. In a perfect world, that would be the source > you want to use, but in reality all it tells you is which mirror's > firewall/etc. responds to ping fastest. > What happens is the server is either lagging or becomes overloaded > fast (possibly because many users are trying to update from it) so > the speed goes down the drain. > End result: I have 3mb download on my DSL line, but using the "fastest > mirror" often gives me 50K (or even lower) download speed. Sometimes I > end up editing the timedhosts.txt file and faking a long timeout value > for the slow host. > > > I turned it off for exactly the reason you cite above. This isn't a measure of a fastest mirror. I think it would be really great if yum would keep track of the mirrors used and the actual download rate obtained over time with each mirror. It would have to be a weighted update of speed averaging past total at past speed and current total and current speed. Then instead of always using the fastest mirror, take the top N (20?, user selectable?) fastest mirrors and share the load among them. Set a size threshold so that only files above a certain size (2 MB?, 1MB?, 500K?) are taken from the fastest mirrors, let any other files come from anywhere. If a file is 20K in size, the speed of the download isn't really relevant. This shares the load and ensures that certain servers don't get hit by everyone, thus degrading their performance and stressing them unfairly. I've thought about writing a plugin to do this, but haven't made it yet. The fastest mirror plugin would be a good template. Mostly, I have just decided to run yum manually at slack times when it doesn't matter how fast it is, and it just does its thing. On a related note, it would be nice if at some level of logging, yum printed the url of the mirror used for the download with the download rate. Then I could create my own crude version of the above algorithm just by parsing the log output and creating my own database or file with the information. -- fedora-list mailing list fedora-list@xxxxxxxxxx To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
