Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261516AbVAGQxC (ORCPT ); Fri, 7 Jan 2005 11:53:02 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261515AbVAGQxB (ORCPT ); Fri, 7 Jan 2005 11:53:01 -0500 Received: from clock-tower.bc.nu ([81.2.110.250]:27841 "EHLO localhost.localdomain") by vger.kernel.org with ESMTP id S261507AbVAGQuR (ORCPT ); Fri, 7 Jan 2005 11:50:17 -0500 Subject: Re: Make pipe data structure be a circular list of pages, rather than From: Alan Cox To: Oleg Nesterov Cc: Linus Torvalds , William Lee Irwin III , Linux Kernel Mailing List In-Reply-To: <41DE9D10.B33ED5E4@tv-sign.ru> References: <41DE9D10.B33ED5E4@tv-sign.ru> Content-Type: text/plain Content-Transfer-Encoding: 7bit Message-Id: <1105110401.17166.346.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 (1.4.6-2) Date: Fri, 07 Jan 2005 15:45:58 +0000 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 731 Lines: 17 On Gwe, 2005-01-07 at 14:30, Oleg Nesterov wrote: > will block after writing PIPE_BUFFERS == 16 characters, no? > And pipe_inode_info will use 64K to hold 16 bytes! > > Is it ok? That would break stuff, but holding the last page until it fills 4K would work, or just basic sg coalescing when possible. The pipe behaviour - particularly size and size of atomic writes is defined by SuS and there are people who use pipes two ways between apps and use the guarantees to avoid deadlocks - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/