From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id EAEBF6B0253 for ; Tue, 25 Oct 2016 03:22:20 -0400 (EDT) Received: by mail-pf0-f198.google.com with SMTP id e6so135347294pfk.2 for ; Tue, 25 Oct 2016 00:22:20 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [2001:1868:205::9]) by mx.google.com with ESMTPS id ro4si16091930pab.36.2016.10.25.00.22.20 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 25 Oct 2016 00:22:20 -0700 (PDT) Date: Tue, 25 Oct 2016 00:21:22 -0700 From: Christoph Hellwig Subject: Re: [PATCHv4 18/43] block: define BIO_MAX_PAGES to HPAGE_PMD_NR if huge page cache enabled Message-ID: <20161025072122.GA21708@infradead.org> References: <20161025001342.76126-1-kirill.shutemov@linux.intel.com> <20161025001342.76126-19-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161025001342.76126-19-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: Theodore Ts'o , Andreas Dilger , Jan Kara , Andrew Morton , Alexander Viro , Hugh Dickins , Andrea Arcangeli , Dave Hansen , Vlastimil Babka , Matthew Wilcox , Ross Zwisler , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org On Tue, Oct 25, 2016 at 03:13:17AM +0300, Kirill A. Shutemov wrote: > We are going to do IO a huge page a time. So we need BIO_MAX_PAGES to be > at least HPAGE_PMD_NR. For x86-64, it's 512 pages. NAK. The maximum bio size should not depend on an obscure vm config, please send a standalone patch increasing the size to the block list, with a much long explanation. Also you can't simply increase the size of the largers pool, we'll probably need more pools instead, or maybe even implement a similar chaining scheme as we do for struct scatterlist. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org