Return to BSD News archive
Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!news.cs.su.oz.au!metro!metro!asstdc.scgt.oz.au!nsw.news.telstra.net!act.news.telstra.net!imci3!imci4!newsfeed.internetmci.com!news.kei.com!nntp.coast.net!swidir.switch.ch!serra.unipi.it!labinfo.iet.unipi.it!luigi From: luigi@labinfo.iet.unipi.it (Luigi Rizzo) Newsgroups: comp.unix.bsd.freebsd.misc Subject: Re: FreeBSD as a router Date: 9 May 1996 19:09:04 GMT Organization: Dip. di Ingegneria dell'Informazione, Univ. di Pisa Lines: 23 Distribution: world Message-ID: <4mtfsg$14l8@serra.unipi.it> References: <4lfm8j$kn3@nuscc.nus.sg> <317CAABE.7DE14518@FreeBSD.org> <4lt098$erq@itchy.serv.net> <Pine.SUN.3.90.960427140735.3161C-100000@tulip.cs.odu.edu> <4mj7f2$mno@news.clinet.fi> <318E6BB1.6A71C39B@lambert.org> NNTP-Posting-Host: labinfo.iet.unipi.it In article <318E6BB1.6A71C39B@lambert.org>, Terry Lambert <terry@lambert.org> writes: |> cards in the machine, and don't buy shared interrupt boards from |> the Intel OEM products division, buy the discrete interrupt ones |> from their server products division). I think that shared interrupts are not that terrible. For every interrupt (which has a relatively high OS overhead anyways) you just have to check every board in the chain to see which one generated the interrupt. Since this should cost roughly a procedure call/return for each board, and I doubt that you have to walk more than 3-4 boards anyways, my feeling is that shared interrupts are costing you about one microsecond (or less) per interrupt WRT non-shared interrupts. Anything wrong with this reasoning ? Luigi -- ==================================================================== Luigi Rizzo Dip. di Ingegneria dell'Informazione email: luigi@iet.unipi.it Universita' di Pisa tel: +39-50-568533 via Diotisalvi 2, 56126 PISA (Italy) fax: +39-50-568522 http://www.iet.unipi.it/~luigi/ ====================================================================