From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Wolfgang Jenkner Newsgroups: gmane.comp.lib.glibc.alpha,gmane.emacs.devel Subject: Re: Removal of unexec support from glibc malloc Date: Tue, 19 Jan 2016 14:27:21 +0100 Message-ID: <85oachlmx2.fsf@iznogoud.viz> References: <569CDB81.6040600@redhat.com> <569D3BE0.6050103@cs.ucla.edu> <569D4207.4060209@cs.ucla.edu> <83mvs2d5b2.fsf@gnu.org> <858u3meiv1.fsf@iznogoud.viz> <569D6A3E.2010009@cs.ucla.edu> <569D73D7.1080206@redhat.com> <569DD82B.20201@cs.ucla.edu> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1453210062 29173 80.91.229.3 (19 Jan 2016 13:27:42 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 19 Jan 2016 13:27:42 +0000 (UTC) Cc: Florian Weimer , Eli Zaretskii , Emacs-devel@gnu.org, GNU C Library To: Paul Eggert Original-X-From: libc-alpha-return-66409-glibc-alpha=m.gmane.org@sourceware.org Tue Jan 19 14:27:38 2016 Return-path: Envelope-to: glibc-alpha@plane.gmane.org Original-Received: from server1.sourceware.org ([209.132.180.131] helo=sourceware.org) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1aLWJs-0008V5-EM for glibc-alpha@plane.gmane.org; Tue, 19 Jan 2016 14:27:36 +0100 DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:references:date:message-id :mime-version:content-type; q=dns; s=default; b=HDDvMa7pv0Bj3/Ir E60r64qo/RYkRoVJZOygxSAY8JTE0uKsf9ibkky55KcuSNZXT0SbyuQ4IWIu/41u oEiT8lbFiozAcZcOsPzW7jozb202J7+2rn0sGTvMKzzlNAufuludzuju2b2tbkiE yIRuS8+wGy9qxR9lLFgHqWPjZvY= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:references:date:message-id :mime-version:content-type; s=default; bh=oDlrzT2i1ONfTY8RcBj7Qc RxoAs=; b=H4M90J5m2Gi//GH2IOBXAE1Non+W/M0m17ro5pBZ2QUtihT7cLCWq/ 7cz5ulYY/DStTkJTs08ZdwzmcaYcqnQ9/r+NPWSNYOEnHkICNI/8qmWEmeHGCR80 p3/a6KnpaToakSJv/tSIFmBP5XjnJKfu0i6Z74Xw9XQ9UttFjdvFU= Original-Received: (qmail 122151 invoked by alias); 19 Jan 2016 13:27:30 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Original-Sender: libc-alpha-owner@sourceware.org Original-Received: (qmail 122121 invoked by uid 89); 19 Jan 2016 13:27:29 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.9 required=5.0 tests=BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RCVD_IN_DNSWL_NONE autolearn=no version=3.3.2 spammy=H*r:FreeBSD, H*r:4.86 X-HELO: b2bfep12.mx.upcmail.net X-SourceIP: 91.119.110.52 Mail-Followup-To: Paul Eggert , Florian Weimer , Eli Zaretskii , Emacs-devel@gnu.org, GNU C Library User-Agent: Gnus/5.130014 (Ma Gnus v0.14) Emacs/25.1.50 (berkeley-unix) Xref: news.gmane.org gmane.comp.lib.glibc.alpha:58692 gmane.emacs.devel:198351 Archived-At: On Mon, Jan 18 2016, Paul Eggert wrote: > ./configure emacs_cv_var_doug_lea_malloc=no > > This causes Emacs to use its own malloc implementation. Back then > I observed that this hurt performance somewhat (text 0.5% larger, data > 7.6% larger, 14% more CPU time on my usual benchmark) but I did not > observe any bugs; see > . IIUC, this means that either mmap or src/ralloc.c is needed for memory reallocations, and those do have very annoying performance problems in non-contrived cases, please see bug#19393 for such a scenario. The discussion about the performance problem begins at http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19393#46