site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com On Apr 11, 2008, at 1:12 AM, Justin C. Walker wrote: On Apr 10, 2008, at 10:35 , Michael Cashwell wrote: On Apr 10, 2008, at 11:44 AM, Justin C. Walker wrote: In terms of any code at issue for rimas' problem, yes. -Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... You are correct that an ethernet driver does not have permission to drop one kind of packet over another, I don't think you are correct in your implication that it cares about network-layer packet types Did I imply it does? I didn't intend to. You did say that the driver should not have "more permission" to drop UDP over TCP packets. I don't know of any driver that pays attention to IP frame type (in particular because they can't always tell; as you say, fragmentation is fun). OK, that was only in reference to an implication that I took from William's post that the loss was OK simply because the data were UDP even if it was happening in the driver. We are pretty clearly in violent agreement here. I don't think TCP/UDP or QoS is involved in rimas' problem. That really does look like a driver issue. I don't think so, although I suppose it's worth looking at. The driver can only do so much; it's part of a bucket brigade, and if it doesn't have buffers, that's it for the outgoing packets. The driver has no clue where the packets come from; it's just all bits to it. I'm thinking in the area of the driver not servicing the hardware often enough and the loss actually occurs in the Ethernet controller hardware. But I'd see that as a driver issue since servicing the hardware is its job. It may just be a buffer reservation problem though. Assuming that someone's data is less important just because they used UDP is flawed. I don't think there is any assumption regarding that except in the UDP code, where it's assumed that if there's no space for the packet, it's OK to drop it. I'd just run across the "UDP == throw-away" mindset in William's post in other contexts (mainly sysadmins configuring routers) and wanted to point out that it's not really correct in all cases. This email sent to site_archiver@lists.apple.com