From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755461AbYENGsr (ORCPT ); Wed, 14 May 2008 02:48:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751736AbYENGsf (ORCPT ); Wed, 14 May 2008 02:48:35 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:33784 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751673AbYENGse (ORCPT ); Wed, 14 May 2008 02:48:34 -0400 Date: Tue, 13 May 2008 23:33:41 -0700 From: Andrew Morton To: Evgeniy Polyakov Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: POHMELFS high performance network filesystem. Transactions, failover, performance. Message-Id: <20080513233341.47edea7f.akpm@linux-foundation.org> In-Reply-To: <20080513174523.GA1677@2ka.mipt.ru> References: <20080513174523.GA1677@2ka.mipt.ru> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 13 May 2008 21:45:24 +0400 Evgeniy Polyakov wrote: > I'm please to announce POHMEL high performance network filesystem. If any thread takes more than one kmap() at a time, it is deadlockable. Because there is a finite pool of kmaps. Everyone can end up holding one or more kmaps, then waiting for someone else to release one. Duplicating page_waitqueue() is bad. Exporting it is probably bad too. Better would be to help us work out why the core kernel infrastructure is unsuitable, then make it suitable.