Date: Mon, 08 Nov 1999 16:20:38 -0800 From: Douglas Pokorny <dpokorny@pcocd2.intel.com> Cc: Daniel Malament <danielm@j51.com>, questions@FreeBSD.ORG, hardware@FreeBSD.ORG Subject: Re: various Message-ID: <382768D6.3EEF16B3@eng.fm.intel.com> References: <Pine.BSF.4.10.9911070302250.10573-100000@current1.whistle.com>
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Julian Elischer wrote: > > On Sun, 7 Nov 1999, Daniel Malament wrote: > > > I have a number of questions I've been building up... > > > > 1) I have a 2.2.8 box on which I've tried two nics: a generic > > NE2000-compatible PCI (ed1) and a 3com 3c509 ISA (ep0). For comparison, I > > transferred 600M of files to another machine on the network (the only > > other one up right now, in fact). It took half an hour with the PCI. > > (Average of 333 KB/s.) With the 3Com, I didn't let it finish because it > > was giving me transfer rates of 30K/sec!!! Anybody know why I'm getting > > such slow performance out of the 3com? Are all ISA nics this slow? For > > that matter, how much bandwidth can one expect a card to use in general? > > What prevents getting the full 10MB? Buffer delays? > > You should be able to get close to 10Mb/sec on an NE2000 if you have a > pentium200 or more.. > > I suspect the card doing 30KB/sec is configured for the wrong interrupt.. > (check systat -vmstat to se if it's generating any interrrupts) Daniel: I've found that with the 3c509 in particular, configuring it for IRQ9 will always cause this type of slowdown. (Even if there are no other conflictions) Any of the other IRQ's are a better choice. As a result, you may want to see if you're using this interrupt request line. In addition, this card has only 2Kb of buffer memory on it, compared to 16Kb on a NE2000. As a result, many operations (esp. NFS operations which try to send 8Kb of packets at once) will overflow the buffer an often require retransmits. -Douglas --- Douglas R. Pokorny, Systems Analyst, Intel Online Services Inc. I do not speak as a representative of Intel Online Services. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message
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