From owner-freebsd-current Fri Jan 21 18:21:19 2000 Delivered-To: freebsd-current@freebsd.org Received: from gndrsh.dnsmgr.net (GndRsh.dnsmgr.net [198.145.92.4]) by hub.freebsd.org (Postfix) with ESMTP id 2F27B15425; Fri, 21 Jan 2000 18:21:11 -0800 (PST) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: (from freebsd@localhost) by gndrsh.dnsmgr.net (8.9.3/8.9.3) id SAA59574; Fri, 21 Jan 2000 18:19:39 -0800 (PST) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <200001220219.SAA59574@gndrsh.dnsmgr.net> Subject: Re: Please help spread the CVSup mirror load more evenly In-Reply-To: from Chuck Robey at "Jan 21, 2000 08:56:29 pm" To: chuckr@picnic.mat.net (Chuck Robey) Date: Fri, 21 Jan 2000 18:19:39 -0800 (PST) Cc: obrien@FreeBSD.ORG (David O'Brien), current@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL54 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > On Fri, 21 Jan 2000, David O'Brien wrote: > > > On Fri, Jan 21, 2000 at 07:03:51PM -0500, Chuck Robey wrote: > > > I don't know ... I think it might be a good idea for the cvsup client to > > > make a connection to a cvsup master, get redirected from that master to > > > the actual handler of the connection, and then work. That way, a config > > > file on the master could be set up to know the capabilities of the other > > > machines (network availability, machine speed, etc) and dole out > > > connections weighted on that. > > > > How is a cvsup master to know anything about the path from me to any > > given cvsup mirror? Knowing something about the path from me to the > > master and the path from the master to the mirror tells zero about the > > path from me to the mirror. > > > > Being on an .EDU network, I have a *very* different path to other .EDU > > machine participating in Inetnet2. My path to cvsup3 is a prime example. > > This "cvsup master" will have no idea about this. > > I guess it means, is the main component trying to be balanced the server > resources or the network resources. I may be wrong, but I think that the > server resources are more likely to be the most important bottleneck, and > this method detects that, with minimal network effects. > > If you think that it's really the network that's going to be the > bottleneck, then you wouldn't want to use this method. I don't think I'm > wrong, but I'm willing to listen to arguments on it. I think, and am pretty sure as hostmaster for cvsup4, that the bottleneck is a combination of both. We use the max connection limit to control the load on the server, and simply refuse connections beyond the acceptable load limit. As far as I know none of the servers run unlimited connection counts so we already have a load controlling mechanism. I know from a network bandwidth point of view I can tell when someone with T-1 or better comes on and pulls a full copy from us, it shows up quite nicely in the load graphs. I also know from looking at our logs that some people would get faster cvsup's if they changed which mirror they are pulling from. (Anyone directly attached to Verio should no longer be using us, but the new Verio provided server instead.) -- Rod Grimes - KD7CAX @ CN85sl - (RWG25) rgrimes@gndrsh.dnsmgr.net To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message