From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760120AbYEXATW (ORCPT ); Fri, 23 May 2008 20:19:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753238AbYEXATP (ORCPT ); Fri, 23 May 2008 20:19:15 -0400 Received: from an-out-0708.google.com ([209.85.132.243]:3172 "EHLO an-out-0708.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752914AbYEXATO (ORCPT ); Fri, 23 May 2008 20:19:14 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=PdChcavu9xAaIOokJTRYqW+wRhldl7JG0DGV5th17gP3j8haD0VZ8w0OZNbD6hkftj4quuH5nUY+s/gg/plqmE74T4C2ygBt9WloQ47kHSrVOY+bwXWcf7PxOWrTcTktG+pmqr37vZ5Hb9L/mxjPk76/VsJUTa1b92ZdJjKFLL8= Message-ID: Date: Fri, 23 May 2008 21:19:13 -0300 From: "Fausto Richetti Blanco" To: linux-kernel@vger.kernel.org Subject: Pipe buffers' limit of 16 * 4K In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello guys, I'm working with a 2.6.9 kernel (ok, I know it's quite old) and faced a problem with the 4K (one page) buffer limit for the pipes. I've found that in the 2.6.11 the pipes' buffers were changed to a circular list of pages which increased this limit to 16 * 4K. This limit is hardcoded here /usr/src/linux/include/linux/pipe_fs_i.h:6 #define PIPE_BUFFERS (16) Is there a reason for this not to be an adjustable parameter (eg.: by an ulimit in the userspace) ? Can you please CC me on the answer ? Thanks in advance, Fausto Richetti Blanco