From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9754 invoked by alias); 14 Sep 2012 19:27:07 -0000 Received: (qmail 9731 invoked by uid 22791); 14 Sep 2012 19:27:06 -0000 X-SWARE-Spam-Status: No, hits=-3.8 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00,KHOP_THREADED X-Spam-Check-By: sourceware.org Received: from localhost (HELO sourceware.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 14 Sep 2012 19:26:53 +0000 From: "bugdal at aerifal dot cx" To: glibc-bugs@sources.redhat.com Subject: [Bug malloc/14581] glibc leaks memory and do not reuse after free (leading to unlimited RSS growth) Date: Fri, 14 Sep 2012 19:27:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: malloc X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: bugdal at aerifal dot cx X-Bugzilla-Status: NEW X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: CC Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact glibc-bugs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: glibc-bugs-owner@sourceware.org X-SW-Source: 2012-09/txt/msg00119.txt.bz2 http://sourceware.org/bugzilla/show_bug.cgi?id=14581 Rich Felker changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |bugdal at aerifal dot cx --- Comment #1 from Rich Felker 2012-09-14 19:26:39 UTC --- Is this supposed to be a bug report or a trick question for CS students? :) You claimed "there is no heap fragmentation", but the allocation/free pattern you're performing seems like a classic fragmentation stress test pattern. There is no general-purpose allocation strategy that can avoid all instances of pathological fragmentation, and this pattern is one that would be especially hard to avoid without having special-cased it (and probably making malloc behavior much worse for common real-world cases). Did you run into this issue in a real-world application, or did you construct this test as a worst-case? By the way, the pathological fragmentation observed here does not seem specific to glibc. It seems like it will occur with any allocator utilizing the basic dlmalloc strategy. I just confirmed that the same issue happens with ours in musl libc. -- Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.