Date: Sun, 1 Apr 2001 22:36:43 +0200 (CEST) From: Bert Driehuis <driehuis@playbeing.org> To: "Jason T. Luttgens" <lucky@lansters.com> Cc: freebsd-stable@freebsd.org Subject: RE: Network performance question Message-ID: <Pine.BSI.4.21.0104012230300.4361-100000@c1111.nl.compuware.com> In-Reply-To: <000001c0bae7$d315d910$0200010a@lucky>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sun, 1 Apr 2001, Jason T. Luttgens wrote: > >Send a predictable load to the device under test (say, include a > >sequence number) and use that to determine packet loss (and, also > >interesting, packet loss patterns). > > Well, I thought that I was doing this by using a known set of data from the > tcpdump I captured earlier and was replaying. Each time it replays, it is > the same number of packets and payload content. The network I am testing on > is isolated (not connected to anything else but these two computers). > > I'm not sure I see the difference between what you describe and what I did. > What do I need to do to create the environment you mention? Number the packets sequentially, and read the tcpdump recording on the receiving end. There is a huge difference between a driver crapping out halfway through or one dropping every twelfth packet. I've seen Ethernet drivers shut down for an X amount of time until a deadman timer restarts it, and finding gaps in the data is an indication of that. Cheers, -- Bert -- Bert Driehuis -- driehuis@playbeing.org -- +31-20-3116119 If the only tool you've got is an axe, every problem looks like fun! To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSI.4.21.0104012230300.4361-100000>