From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ad van den Broek Subject: PIPE questions for Linux 2.4 setup Date: Thu, 21 May 2009 16:56:36 +0200 Message-ID: <9f924d250905210756l5db654abkf9c9fbc4170717ac@mail.gmail.com> Reply-To: AdvandenBroek.nl@gmail.com Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:reply-to:date:message-id :subject:from:to:content-type:content-transfer-encoding; bh=mXcuVyFuz7N6A3A/TGmayos20ZbiiClaEW4wtt8li+Q=; b=XlVs1rgzUlGrQpdaxY6NpNzHQMy+2HSv2JwRkX2u3SxX0pKBrctEria+3KgowW7LOK XhUpzhPSjxILnkM9KFAlIROyEGLwqKclyM/kQyL2J77B35x1+zmQkbsoM4yAvX5gnCsi eTKNnlWz5LKs2uh3p5XWmZ97nmfQdOe842hS8= Sender: linux-c-programming-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: linux-c-programming@vger.kernel.org Dear C/Linux friends, We wanted to increase PIPE_SIZE (from 4K to 8K on linux 2.4 on an AMD LX800 system). The result is a segmentation error as soon as Read() is reading more data than 4K from the pipe. So pipe data seems to be damaged. If we change PIPE_SIZE back tot 4K everything is running fine. Question-1: Any suggestion to prevent this segmentation error ? * PIPE_SIZE If you look in the linux kernel code for PIPE_SIZE ("include/linux/pipe_fs_i.h") you find: #define PIPE_SIZE PAGE_SIZE I don't know if #define PIPE_SIZE PAGE_SIZE is necessary or just a simple shortcut. Question-2: Is it OK if PIPE_SIZE > PAGE_SIZE ? * PAGE_SIZE Question-3: Is it OK to increase Page_size on linux 2.4 on AMD LX800 system ? Which aspects are limiting the user to config the PAGE_SIZE ? -- With best regards, Ad van den Broek