From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7101 invoked by alias); 23 Apr 2004 17:09:15 -0000 Mailing-List: contact libc-hacker-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-hacker-owner@sources.redhat.com Received: (qmail 7085 invoked from network); 23 Apr 2004 17:09:14 -0000 Received: from unknown (HELO sunsite.ms.mff.cuni.cz) (195.113.15.26) by sources.redhat.com with SMTP; 23 Apr 2004 17:09:14 -0000 Received: from sunsite.ms.mff.cuni.cz (sunsite.mff.cuni.cz [127.0.0.1]) by sunsite.ms.mff.cuni.cz (8.12.8/8.12.8) with ESMTP id i3NEvT3j029703; Fri, 23 Apr 2004 16:57:29 +0200 Received: (from jakub@localhost) by sunsite.ms.mff.cuni.cz (8.12.8/8.12.8/Submit) id i3NEvOWn029615; Fri, 23 Apr 2004 16:57:24 +0200 Date: Fri, 23 Apr 2004 17:09:00 -0000 From: Jakub Jelinek To: Mark Brown Cc: aj@suse.de, Glibc hackers Subject: Re: AIO work in librt Message-ID: <20040423145724.GM5191@sunsite.ms.mff.cuni.cz> Reply-To: Jakub Jelinek References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4i X-SW-Source: 2004-04/txt/msg00088.txt.bz2 On Fri, Apr 23, 2004 at 11:17:09AM -0500, Mark Brown wrote: > Given this conversation from last year: > > Andreas Jaeger wrote: > > Ulrich Drepper writes: > > > Andreas Jaeger wrote: > > >> AFAIK Ben's kernel level implementation is in current 2.5 kernels. > > >> Can we base now a glibc implementation on this? Anybody already > > >> working on this? > > > > > > I doN't think the kernel side is complete enough. > > > > Ben, what is still missing on the kernel side? Looking at fs/aio.c I > > thought it was complete. > > We are thinking about making this work in librt (and submitting it, of > course). > Andreas, did you learn anything from Ben? Anyone else know of a > factor that keeps this from being able to work? RHEL glibc already includes the rtkaio glibc add-on which is librt using the kernel AIO interface. Unfortunately, the kernel side is very limited and doesn't have good support for the things userland POSIX AIO needs (e.g. in the area of notification and cancellation, or that many things are serialized in the kernel rather than truely asynchronous; and from what I've heard the 2.6 aio is even in worse shape than what we used to have in 2.4.x RHEL kernels). Jakub