On Tue, Oct 23, 2007, Sam Stickland wrote:
I'm concerned that if Microsoft were to post this as a patch to Windows XP/2003 then we would see the effects of this "all at once", instead of the gradual process of Vista deployment. Anyone agree?
You need both ends to have large buffers so TCP window sizes can grow. So a few possibilities: * you're running content servers but you're on training wheels and you're just not aware of this. Windows default sizes are small, so you never notice as you never grow enough TCP windows to fill your set buffer size. These guys would notice if Windows XP was patched to use larger/adaptive buffering. * You're cluey and already have window sizes tuned; these guys won't notice any client changes as they'll never negotiate a larger window. * You're cluey and have assumed X% of your customers (say, the ones >100ms away from you) have fixed their window sizes and hedge your bets on that. This group is analogous to network engineering based on current, not future use - possibly saving money in the short term, but probably going to fund the executive bonuses and not put away safely for days like what you're suggesting. * .. caveat to the above: until Linux goes and does what Linux does best and change system defaults; enabling adaptive socket buffers by default during a minor version increment. Anyone remember ECN? :P Then even some cluey server admins will cry in pain a little. * I don't think the proposals are changing TCP congestion avoidance/etc, are they? Its easily solvable - just drop the window sizes. In fact, I think the window size increase/adaptive window size stuff would be much more useful for P2P over LFN than average websites -> clients. General page HTTP traffic atm doesn't hit window size before the reply has completed. Sites serving larger content than HTML+images (say, Youtube, Music sites, etc) would've already given this some thought and fixed their servers to not run out of RAM so easily. Those are on a CDN anyway.. Its not just that; there's other things to worry about than just numsockets * (send size + receive size) memory possibly being consumed but its a good starting point. 2c, Adrian