Date: Sun, 15 Nov 1998 10:45:49 -0800 (PST) From: Archie Cobbs <archie@whistle.com> To: brian@Awfulhak.org (Brian Somers) Cc: cshenton@uucom.com, dave@comsite.net, questions@FreeBSD.ORG Subject: Re: mpd + EQL, Livingston PM2 MLLB, alternatives? mpd load high? Message-ID: <199811151845.KAA02134@bubba.whistle.com> In-Reply-To: <199811150024.AAA26739@woof.lan.awfulhak.org> from Brian Somers at "Nov 15, 98 00:24:46 am"
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Brian Somers writes: > > > Archie: I notice mpd with one line is consuming 10-15% of my 486-66 > > > CPU when doing stuff like CVSUP or FTP downloads. Is this normal? Due > > > to the link compression? Will it increase as I add lines? The 486 is > > > pretty much dedicated to being a dialup/router so this isn't a big > > > concern but it does indicate scalability problems if I try to > > > increase lines (or use even older hardware :-) > > > > That's probably more or less normal.. the negative side of > > doing it all in user-land. > > A recent report from jak@cetlink.net (John Kelly) said about > user-ppp: > > : >CPU loading under FTP is good with only one link in the bundle. The > : >server ppp consumes about 2% of the CPU and the client about 4%. But > : >when I add a second link to the bundle, the client ppp skyrockets to > : >over 40% of the CPU. Ouch! > : > : I tried reversing the roles of client and server, and the problem > : disappeared?! Realizing that, I started swapping things and found > : that one cable was causing the problem. It was not obvious, because > : throughput was fine with that cable. But something about it is flakey > : and causing the CPU load to shoot way up. > : > : Now that I've replaced that cable, CPU loading is much better. With > : two lines running full blast at 115,200, the client tops out around 9% > : and the server about 7%. It goes much higher with compression, but I > : can let the modems do the compression and save my CPU to run about 16 > : lines. > > Maybe there's a similar problem with cabling here ? Definitely could be.. for example, if you're not getting proper flow control signals (RTS/CTS), or one of the data lines is flakey and you get lots of corrupted packets, ... -Archie ___________________________________________________________________________ Archie Cobbs * Whistle Communications, Inc. * http://www.whistle.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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