From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: David Kastrup Newsgroups: gmane.lisp.guile.user Subject: Re: out-of-control GC Date: Sun, 10 Sep 2017 20:03:57 +0200 Organization: Organization?!? Message-ID: <877ex6zb02.fsf@fencepost.gnu.org> References: <87zia28phj.fsf@web.de> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1505320173 12264 195.159.176.226 (13 Sep 2017 16:29:33 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 13 Sep 2017 16:29:33 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.0.50 (gnu/linux) To: guile-user@gnu.org Original-X-From: guile-user-bounces+guile-user=m.gmane.org@gnu.org Sun Sep 10 20:05:20 2017 Return-path: Envelope-to: guile-user@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dr6bV-0002kZ-MV for guile-user@m.gmane.org; Sun, 10 Sep 2017 20:05:09 +0200 Original-Received: from localhost ([::1]:53813 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dr6bd-0000GW-0y for guile-user@m.gmane.org; Sun, 10 Sep 2017 14:05:17 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:36803) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dr6bH-0000FD-29 for guile-user@gnu.org; Sun, 10 Sep 2017 14:04:55 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dr6bD-0001zA-UL for guile-user@gnu.org; Sun, 10 Sep 2017 14:04:55 -0400 Original-Received: from [195.159.176.226] (port=47601 helo=blaine.gmane.org) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1dr6bD-0001y3-Nf for guile-user@gnu.org; Sun, 10 Sep 2017 14:04:51 -0400 Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1dr6aV-0008Ej-KB for guile-user@gnu.org; Sun, 10 Sep 2017 20:04:07 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 31 Original-X-Complaints-To: usenet@blaine.gmane.org X-Face: 2FEFf>]>q>2iw=B6, xrUubRI>pR&Ml9=ao@P@i)L:\urd*t9M~y1^:+Y]'C0~{mAl`oQuAl \!3KEIp?*w`|bL5qr,H)LFO6Q=qx~iH4DN; i"; /yuIsqbLLCh/!U#X[S~(5eZ41to5f%E@'ELIi$t^ Vc\LWP@J5p^rst0+('>Er0=^1{]M9!p?&:\z]|;&=NP3AhB!B_bi^]Pfkw Cancel-Lock: sha1:fH/TDstgiT0DIUUiWQzXsesd74E= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 195.159.176.226 X-BeenThere: guile-user@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: General Guile related discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guile-user-bounces+guile-user=m.gmane.org@gnu.org Original-Sender: "guile-user" Xref: news.gmane.org gmane.lisp.guile.user:14129 Arne Babenhauserheide writes: > Hi Linas, > > > Linas Vepstas writes: > >> To make this conversation less crazy, and more down-to-earth, here is a >> demo that seems to spend most of its time in GC. Hard for me to to say that >> this is "wrong", right now, but it illustrates the scandalous nature of the >> problem. > > Do you have many string operations in your code? > > If I replace > > (cons (format #f "~A" cnt) lis) > > with > > (cons cnt lis) > > GC is down to ~20% (from around 130%). But the main point of using format (rather than string appends) is to avoid creating lots of garbage-collected temporary expressions. A factor of 6 seems to suggest that this expectation is not actually being accommodated. -- David Kastrup