Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264494AbTFKVun (ORCPT ); Wed, 11 Jun 2003 17:50:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264498AbTFKVun (ORCPT ); Wed, 11 Jun 2003 17:50:43 -0400 Received: from hq.pm.waw.pl ([195.116.170.10]:65213 "EHLO hq.pm.waw.pl") by vger.kernel.org with ESMTP id S264494AbTFKVum (ORCPT ); Wed, 11 Jun 2003 17:50:42 -0400 To: "David Schwartz" Cc: Subject: Re: select for UNIX sockets? References: From: Krzysztof Halasa Date: 12 Jun 2003 00:04:21 +0200 In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1620 Lines: 43 "David Schwartz" writes: > Looks like another receive queue to me. There is no send queue and you > wouldn't want there to be one. So? > They have device queues, they have no socket send queues. Well? > > Having no per-sender socket queue for UDP/IP is totally irrelevant here. > > It is relevent. Because when you select for write, you're trying to > find > out whether there's space to write to the socket. Which socket? IP/UDP or UNIX one? You know, UNIX sockets are a little special - both ends are on the same machine. This is why the sending routine can check the receiving queue length. > That would require there > to be something for there to be space in or not to be space in. Whatever you > want to call that (I call it a 'socket send queue', but it doesn't matter) > that queue doesn't exist for UDP and you wouldn't want it to exist. Sure. > With UDP, or any connectionless protocol, the application is ultimately > responsible for transmit pacing. Still, this is all irrelevant, this is a kernel-only issue. > You could argue that it would be nice if > the kernel helped out more than it currently does, but it has no obligation > to do so. You're missing the fact that the kernel _has_ code to help but this _existing_ code is broken (and yes, it was fine in earlier kernels). -- Krzysztof Halasa Network Administrator - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/