From owner-freebsd-hackers Tue May 1 1:23:21 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from cslab.csie.ntu.edu.tw (cslab.csie.ntu.edu.tw [140.112.30.25]) by hub.freebsd.org (Postfix) with ESMTP id A1ED537B422 for ; Tue, 1 May 2001 01:22:53 -0700 (PDT) (envelope-from r88074@csie.ntu.edu.tw) Received: from hornets (hornets.csie.ntu.edu.tw [140.112.30.134]) by cslab.csie.ntu.edu.tw (8.9.3/8.9.3) with SMTP id QAA17927 for ; Tue, 1 May 2001 16:22:36 +0800 (CST) Message-Id: <200105010822.QAA17927@cslab.csie.ntu.edu.tw> From: "ªL­^¶W" To: "Freebsd-Hackers" Subject: RE: write() vs aio_write() Date: Tue, 1 May 2001 16:21:21 +0800 X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-Reply-To: <20010430173555.H18676@fw.wintelcom.net> X-MimeOLE: Produced By Microsoft MimeOLE V4.72.3110.3 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG -----Original Message----- From: owner-freebsd-hackers@FreeBSD.ORG [mailto:owner-freebsd-hackers@FreeBSD.ORG]On Behalf Of 'Alfred Perlstein' Sent: Tuesday, May 01, 2001 8:36 AM To: Charles Randall Cc: ªL­^¶W; Freebsd-Hackers Subject: Re: write() vs aio_write() * Charles Randall [010430 10:26] wrote: > Regarding aio_*, Alfred Perlstein writes: > >It's a good idea to use it for disk IO, probably not a good > >idea for network IO. > > Could you elaborate? Sure. Network IO can be done without blocking (unless you take a fault on the source address of your data). Hence the additional context switching required by aio is not needed. Disk IO probably stands a good chance of blocking your application, if you can offload that blocking to a kernel thread you should be able to continue serving content. By the way..... I think synchonous I/O include blocking and non-blocking I/O and asynchonous I/O is non-blocking I/O, but it is signal-driven......... Am I right ???? -- -Alfred Perlstein - [alfred@freebsd.org] Instead of asking why a piece of software is using "1970s technology," start asking why software is ignoring 30 years of accumulated wisdom. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message