* Shawn Walker <[EMAIL PROTECTED]> [2008-07-17 17:25]: > Stephen Hahn wrote: >> * Shawn Walker <[EMAIL PROTECTED]> [2008-07-16 22:28]: >>> 3) Automatic "preferred" mirror selection >>> >>> There are a number of techniques that I've seen used over the years to >>> determine the best mirror to connect to. I've seen package managers use >>> average ping time, average transfer speed, round-robin, and even random >>> selection to determine which mirror to use from an available list. >>> >>> One thought that occurred to me today was to base selection on closest >>> timezone (a mirror in the same timezone as you is likely to provide a >>> better experience than one in another timezone). >>> >>> In fact, a combination of techniques could be used to isolate the best >>> one to mark as the preferred mirror. For example, we could get the >>> mirrors in the same timezone first (then move up to the next greater >>> criteria), then check response time, then check speed, etc. until we >>> narrow it down to a specific one. >> >> My guess is that your timezone proposal is to manage congestion. I'm > > No, actually. It was my cheap hack to get around the fact that you can't > reliably detect the client's geographical location relative to the server. > Strictly looking at the US for a moment, it is very likely that a server in > the US/Central timezone (as an example) would give me a better network > response time if I'm actually in the US/Central timezone as well > (physically) than a server in the US/Pacific timezone. > > The time of day is an interesting configuration aspect I hadn't considered, > though as you point out, actual measurements are likely to be more > reliable. > > I had strictly mentioned the timezone as a beginning part of the heuristic. > In other words, if you have a hundred servers to try out, it makes sense > to start with the ones relatively closest to the client. > > I realise timezone is strictly reliable either, but I think it's probably a > good guess most of the time.
If it's not an offset timezone, it might be an interesting hint. As an initial step, let's ask our mirrors for their timezone and compare that to their GeoIP and measured throughput. - Stephen -- [EMAIL PROTECTED] http://blogs.sun.com/sch/ _______________________________________________ pkg-discuss mailing list [email protected] http://mail.opensolaris.org/mailman/listinfo/pkg-discuss
