From: "Amit K. Arora" Subject: Testing ext4 persistent preallocation patches for 64 bit features Date: Wed, 7 Feb 2007 13:18:01 +0530 Message-ID: <20070207074801.GA5419@amitarora.in.ibm.com> References: <20070117094658.GA17390@amitarora.in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: suparna@in.ibm.com, cmm@us.ibm.com, alex@clusterfs.com, suzuki@in.ibm.com To: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org Return-path: Content-Disposition: inline In-Reply-To: <20070117094658.GA17390@amitarora.in.ibm.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org I plan to test the persistent preallocation patches on a huge sparse device, to know if >32 bit physical block numbers (upto 48bit) behave as expected. I have following questions for this and will appreciate suggestions here: a) What should be the sparse device size which I should use for testing? Should a size of > 8TB (say, 100 TB) be enough ? The physical device (backing store device) size I can have is upto 70GB. b) How do I test allocation of >32 bit physical block numbers ? I can not fill > 8TB, since the physical storage available with me is just 70GB. c) Do I need to put some hack in the filesystem code for above (to allocate >32 bit physical block numbers) ? Any further ideas on how to test this will help. Thanks! -- Regards, Amit Arora