Date: Sun, 13 Aug 2000 11:20:01 -0700 (PDT) From: Bruce Evans <bde@zeta.org.au> To: freebsd-bugs@FreeBSD.org Subject: Re: misc/20555: 3C509 driver performance problem Message-ID: <200008131820.LAA24931@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
The following reply was made to PR misc/20555; it has been noted by GNATS. From: Bruce Evans <bde@zeta.org.au> To: xyf@stocke.com Cc: freebsd-gnats-submit@FreeBSD.ORG Subject: Re: misc/20555: 3C509 driver performance problem Date: Mon, 14 Aug 2000 04:19:48 +1000 (EST) On Fri, 11 Aug 2000 xyf@stocke.com wrote: > ab -c 10 -n 10000 http://192.168.1.27/index.html > > they both give me good performance, the result is almost same, but ... > FreeBSD uses more CPU time than Linux, FreeBSD CPU idle is 40%, > Linux CPU idle is 60%, almost 20% CPU lost in FreeBSD! > > I use "top" command and see FreeBSD cost 34% of CPU time in interrupt > handling, the system time is good, only 12%, my net card is old 3COM 3C509, my question is: > > is this the problem of 3C509 driver in FreeBSD or just is more serious FreeBSD design problem? I dodn't see any problem here, except missing accounting for interrupt time in Linux. I think Linux still counts interrupt time against whatever process (including the idle "process") happens to be running when the interrupt occurs. FreeBSD's idle time of 40% is actually the idle time (modulo jitter in the measurement). Linux's idle time of 60% may be mostly spent handling interrupts. Similarly for system and user times. System and user times under Linux are normally larger than under FreeBSD, because parts of them are actually interrupt times. Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200008131820.LAA24931>