From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757199Ab1IALOn (ORCPT ); Thu, 1 Sep 2011 07:14:43 -0400 Received: from 207-126-122-235.ip.openhosting.com ([207.126.122.235]:42773 "EHLO drepperk.user.openhosting.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752944Ab1IALOi (ORCPT ); Thu, 1 Sep 2011 07:14:38 -0400 Message-ID: <4E5F690C.4010209@akkadia.org> Date: Thu, 01 Sep 2011 07:14:20 -0400 From: Ulrich Drepper User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.18) Gecko/20110621 Fedora/3.1.11-1.fc14 Lightning/1.0b3pre Thunderbird/3.1.11 MIME-Version: 1.0 To: Jeremy Allison CC: Andrew Morton , Daniel Ehrenberg , Jens Axboe , Jeff Moyer , linux-kernel@vger.kernel.org, linux-aio@kvack.org Subject: Re: Approaches to making io_submit not block References: <4E5D5817.6040704@kernel.dk> <4E5D64E8.7000102@kernel.dk> <20110830154157.d802d097.akpm@linux-foundation.org> <20110830155438.bc31ab99.akpm@linux-foundation.org> <20110830230342.GB16326@samba2> <20110830161130.592df746.akpm@linux-foundation.org> <4E5E152A.9050804@akkadia.org> <20110831165954.GC1611@samba2> In-Reply-To: <20110831165954.GC1611@samba2> X-Enigmail-Version: 1.1.2 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigF21377A55752E9EF5A0A63F2" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigF21377A55752E9EF5A0A63F2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 08/31/2011 12:59 PM, Jeremy Allison wrote: > I get that, but isn't that what the aio_init(const struct aioinit *init= ) call is meant to > solve ? The problem cannot be solved by something that trivial. Any thread can be delayed indefinitely. If this happens for a file descriptor chances are that all threads for the same file descriptor are affected while there is I/O for all the other file descriptors ready to run. I don't say this is anywhere near optimal or even good, at least it doesn't amplify problems. If you know you want more parallelism on the same file descriptor, dup it. If you don't want anyone like me implementing stupid limitations finally fix the kernel aio interface so that it is usable. --------------enigF21377A55752E9EF5A0A63F2 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.16 (GNU/Linux) iEYEARECAAYFAk5faQwACgkQ2ijCOnn/RHTw3gCfTyA2FJslheyN+jYGbglMuf3D dXEAoLAd0c+zD3sI9YAkY8UcWxgOVYwN =Kkp1 -----END PGP SIGNATURE----- --------------enigF21377A55752E9EF5A0A63F2--