From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gilles Chanteperdrix Subject: Re: Realtime capable userspace? Date: Sun, 14 Apr 2013 12:08:53 +0200 Message-ID: <516A8035.9040604@xenomai.org> References: <516A7083.8080705@meduna.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: "linux-rt-users@vger.kernel.org" To: Stanislav Meduna Return-path: Received: from xenomai.org ([88.191.142.154]:39224 "EHLO xenomai.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750878Ab3DNKVg (ORCPT ); Sun, 14 Apr 2013 06:21:36 -0400 In-Reply-To: <516A7083.8080705@meduna.org> Sender: linux-rt-users-owner@vger.kernel.org List-ID: On 04/14/2013 11:01 AM, Stanislav Meduna wrote: > Hi, > > I know this is not a kernel-related question, but I think the amount of > people doing realtime here is probably the largest. > > As learned the hard-way the glibc is not (yet) realtime capable and > first changes are now starting to trickle in. Even if I try to fix known > places, who knows what, where and for how long is locked. > > What userspace (libc / threads / malloc) are you using for realtime > applications? From my quick research: PI mutexes are not sufficient to make malloc deterministic. I guess if you are looking for a deterministic malloc, you should have a look at TLSF. You can probably get the replacement malloc be used by glibc by using LD_PRELOAD techniques (but OK, it would be just a hack). -- Gilles.