Re: Router take advantage of device polling
Jeffrey, Yes, there is. At a certain level of traffic, network interrupts happen all too often to justify the processing overhead associated with the interrupt service routines, and hence the network activity is best polled. Is 15Mbps the level for enabling polling? Well, this traffic level depends on the underlying hardware capabilities as well. You decide. --Srikanth Jeffrey Lyon wrote: I am currently running a router pushing about 15 megabit of traffic, with CPU usage like so: root 25 5.9 0.0 0 12 ?? WL 10:16AM 47:49.70 (irq7: bge0 amr0) root 14 5.9 0.0 0 12 ?? WL 10:16AM 55:15.63 (swi1: net) root 26 3.0 0.0 0 12 ?? LL 10:16AM 28:42.81 (irq5: bge1) I am told that activating the device_polling kernel option will cause a substantial reduction in this usage. Is there any truth to that statement? Thanks. -- Jeffrey Lyon, Independent Associate jeffreylyon at prepaidlegal.com http://lists.freebsd.org/mailman/listinfo/freebsd-questions http://www.prepaidlegal.com/hub/jeffreylyon Pre-Paid Legal Services, Inc. ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Router take advantage of device polling
I am currently running a router pushing about 15 megabit of traffic, with CPU usage like so: root 25 5.9 0.0 0 12 ?? WL 10:16AM 47:49.70 (irq7: bge0 amr0) root 14 5.9 0.0 0 12 ?? WL 10:16AM 55:15.63 (swi1: net) root 26 3.0 0.0 0 12 ?? LL 10:16AM 28:42.81 (irq5: bge1) I am told that activating the device_polling kernel option will cause a substantial reduction in this usage. Is there any truth to that statement? Thanks. -- Jeffrey Lyon, Independent Associate [EMAIL PROTECTED] http://www.prepaidlegal.com/hub/jeffreylyon Pre-Paid Legal Services, Inc. ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Router take advantage of device polling
On Sat, May 22, 2004 at 06:51:32AM -0400, Jeffrey Lyon wrote: I am currently running a router pushing about 15 megabit of traffic, with CPU usage like so: root 25 5.9 0.0 0 12 ?? WL 10:16AM 47:49.70 (irq7: bge0 amr0) root 14 5.9 0.0 0 12 ?? WL 10:16AM 55:15.63 (swi1: net) root 26 3.0 0.0 0 12 ?? LL 10:16AM 28:42.81 (irq5: bge1) I am told that activating the device_polling kernel option will cause a substantial reduction in this usage. Is there any truth to that statement? Probably not. I see you are using bge(4) devices -- there's nothing in the polling(4) or bge(4) man pages to suggest that the bge interface does support polling, and the code in /usr/src/sys/dev/bge makes no reference to the DEVICE_POLLING cpp macro, so it's unlikely to help with that hardware. Assuming you've got suitable hardware, whether device polling gains you much, or anything at all depends on the nature of the traffic you're dealing with. There are about dozen kernel tunables that you can use to optimize traffic flows. See the polling(4) man page for more information. Cheers, Matthew -- Dr Matthew J Seaman MA, D.Phil. 26 The Paddocks Savill Way PGP: http://www.infracaninophile.co.uk/pgpkey Marlow Tel: +44 1628 476614 Bucks., SL7 1TH UK pgpUU7kuDeBRI.pgp Description: PGP signature