On Wed, Feb 04, 2015 at 01:54:19PM +0900, Teruaki Ishizaki wrote: > (2015/02/02 15:52), Liu Yuan wrote: > >On Tue, Jan 27, 2015 at 05:35:27PM +0900, Teruaki Ishizaki wrote: > >>Previously, qemu block driver of sheepdog used hard-coded VDI object size. > >>This patch enables users to handle "block_size_shift" value for > >>calculating VDI object size. > >> > >>When you start qemu, you don't need to specify additional command option. > >> > >>But when you create the VDI which doesn't have default object size > >>with qemu-img command, you specify block_size_shift option. > >> > >>If you want to create a VDI of 8MB(1 << 23) object size, > >>you need to specify following command option. > >> > >> # qemu-img create -o block_size_shift=23 sheepdog:test1 100M > > > >Is it possible to make this option more user friendly? such as > > > > $ qemu-img create -o object_size=8M sheepdog:test 1G > > At first, I thought that the object_size was user friendly. > But, Sheepdog has already the value of block_size_shift > in the inode layout that means like object_size. > > 'object_size' doesn't always fit right in 'block_size_shift'. > On the other hands, 'block_size_shift' always fit right in > 'object_size'. > > I think that existing layout shouldn't be changed easily and > it seems that it is difficult for users to specify > the object_size value that fit right in 'block_size_shift'. I don't think we need to change the layout. block_size_shift is what QEMU talks to sheep, and QEMU options is what users talks to QEMU. We can convert the user friendly object size into block_size_shift internally in the driver before sending it tosheep daemon, no?
Thanks Yuan
