From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2963 invoked by alias); 29 Nov 2019 08:35:07 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 2948 invoked by uid 89); 29 Nov 2019 08:35:07 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-3.3 required=5.0 tests=AWL,BAYES_00,KAM_NUMSUBJECT,SPF_PASS autolearn=no version=3.3.1 spammy=HX-Languages-Length:994, H*i:sk:874kyna, H*f:sk:874kyna, deprecation X-HELO: albireo.enyo.de From: Florian Weimer To: Joseph Myers Cc: Subject: Re: Update SOMAXCONN value from Linux 5.4 References: <874kynaxro.fsf@mid.deneb.enyo.de> Date: Fri, 29 Nov 2019 08:35:00 -0000 In-Reply-To: <874kynaxro.fsf@mid.deneb.enyo.de> (Florian Weimer's message of "Fri, 29 Nov 2019 09:32:11 +0100") Message-ID: <87zhgf9j2g.fsf@mid.deneb.enyo.de> MIME-Version: 1.0 Content-Type: text/plain X-SW-Source: 2019-11/txt/msg01013.txt.bz2 * Florian Weimer: > * Joseph Myers: > >> Linux 5.4 changes the SOMAXCONN value from 128 to 4096 (this isn't in >> a uapi header; various constants related to the kernel/userspace >> interface, including this one, are in the non-uapi linux/socket.h >> header). >> >> This patch increases the value in glibc. As I understand it, it is >> safe to use a higher value even with older kernels (the kernel will >> simply adjust the value passed to listen to be no more than the value >> supported in the kernel), and SOMAXCONN is actually only a default for >> a sysctl value in the kernel that can be changed at runtime. So I >> think updating the value in glibc is a reasonable and safe thing to >> do. > > Should we add a deprecation warning to the macro and eventually remove > it, given that it's not actually a constant? Oh, I see: POSIX assumes that the implementation uses a constant value for the queue length and requires us to define the macro.