I'm building up to 3000-4000ms latency with these BIB routers. We never had this issue on the old point to points using Cisco gear.
On Wed, Feb 16, 2011 at 5:09 PM, Jim Gettys <j...@freedesktop.org> wrote: > On 02/16/2011 05:44 PM, Mikeal Clark wrote: > >> We just put in a AT&T MPLS and are having a pretty negative experience >> with >> the "Business in a Box" routers they are using for our smaller sites. We >> are seeing extremely high latency under load. Anyone have any experience >> with these devices that could shed some light on this? Are they really >> this >> bad? >> >> > There is excessive buffering in all sorts of devices all over the Internet. > This causes high latency under load (along with higher packet losses, and > lots of other problems. > > It's what I've been blogging about on http://gettys.wordpress.com. These > buffers fill; and they are so large they have defeated TCP congestion > avoidance to boot, with horrifying consequences. > > So far, I've found this problem (almost) everywhere I've looked: > o ICSI has good data that bufferbloat is endemic in DSL, Cable, and > FIOS. Delays are often measured in seconds (rather than milliseconds). > o some corporate and ISP networks run without AQM, in circumstances > that they should. > o Windows, Mac OSX and Linux all have bufferbloat in their network > stacks, at a minimum on recent network device drivers, and often elsewhere. > o Every home router I've tested is horrifyingly bad. > o 3g networks & 802.11 have this in spades. > > Why should AT&T's MPLS be any different? > > My next topic will be "transient" bufferbloat, having to do with defeating > slowstart. > > Come start helping fix this: please join us at bufferbloat.net, as we > try to get people to fix it. Already there are some experimental patches > for the Linux Intel wireless driver. > Jim Gettys > Bell Labs > >