From owner-svn-src-all@freebsd.org Tue Dec 17 18:28:23 2019 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 76E311EEAB4; Tue, 17 Dec 2019 18:28:23 +0000 (UTC) (envelope-from pfg@FreeBSD.org) Received: from smtp.freebsd.org (smtp.freebsd.org [96.47.72.83]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "smtp.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 47cmqC2bQSz4d57; Tue, 17 Dec 2019 18:28:23 +0000 (UTC) (envelope-from pfg@FreeBSD.org) Received: from [192.168.0.5] (unknown [181.52.72.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) (Authenticated sender: pfg) by smtp.freebsd.org (Postfix) with ESMTPSA id D4ADEAD72; Tue, 17 Dec 2019 18:28:22 +0000 (UTC) (envelope-from pfg@FreeBSD.org) Subject: Re: svn commit: r355828 - head/sys/sys To: Cy Schubert Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org References: <201912162355.xBGNtUq6078840@repo.freebsd.org> <201912170442.xBH4gUOg063777@slippy.cwsent.com> From: Pedro Giffuni Organization: FreeBSD Message-ID: Date: Tue, 17 Dec 2019 13:28:20 -0500 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: <201912170442.xBH4gUOg063777@slippy.cwsent.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Dec 2019 18:28:23 -0000 On 16/12/2019 23:42, Cy Schubert wrote: > In message <201912162355.xBGNtUq6078840@repo.freebsd.org>, "Pedro F. > Giffuni" w > rites: >> Author: pfg >> Date: Mon Dec 16 23:55:30 2019 >> New Revision: 355828 >> URL: https://svnweb.freebsd.org/changeset/base/355828 >> >> Log: >> Double the size of ARG_MAX on LP64 platforms. >> >> As modern software keeps growing in size, we get requests to update the >> value of ARG_MAX in order to link the resulting object files. Other OSs >> have much higher values but Increasiong ARG_MAX has a multiplied effect on >> KVA, so just bumping this value is dangerous in some archs like ARM32 that >> can exhaust KVA rather easily. >> >> While it would be better to have a unique value for all archs, other OSs >> (Illumos in partidular) can have different ARG_MAX limits depending on the >> platform, For now we want to be really conservative so we are avoidng >> the change on ILP32 and in the alternative case we only double it since tha >> t >> seems to work well enough for recent Code Aster. >> >> I was planning to bump the _FreeBSD_version but it was bumped recently >> (r355798) so we can reuse the 1300068 value for this change. > This doesn't seem right. Each bump should be for a distinct change and > documented as such. TBH, it is just not worth it: this change will currently benefit only one port (french/aster) and the update won't be committed until after the MFC is done. It is rather more painful that the change only fixes the case for some platforms. Pedro. > Also, it's not like we're saving any build time anyway. sys/syslimits.h > will cause a substantial portion to be rebuilt anyway. > >> >> PR: 241710 >> MFC after: 5 days >> >> Modified: >> head/sys/sys/syslimits.h >> >> Modified: head/sys/sys/syslimits.h >> ============================================================================= >> = >> --- head/sys/sys/syslimits.h Mon Dec 16 23:08:09 2019 (r355827) >> +++ head/sys/sys/syslimits.h Mon Dec 16 23:55:30 2019 (r355828) >> @@ -48,7 +48,11 @@ >> * Do not add any new variables here. (See the comment at the end of >> * the file for why.) >> */ >> -#define ARG_MAX 262144 /* max bytes for an exec functi >> on */ >> +#ifndef __ILP32__ >> +#define ARG_MAX (2 * 256 * 1024) /* max bytes for an exec functi >> on */ >> +#else >> +#define ARG_MAX (256 * 1024) /* max bytes for KVA-starved ar >> chs */ >> +#endif >> #ifndef CHILD_MAX >> #define CHILD_MAX 40 /* max simultaneous processes * >> / >> #endif >> >