Re: [Qemu-devel] Block layer roadmap

[Kevin Wolf]

Am 27.07.2011 14:37, schrieb Stefan Hajnoczi:
> Hi,
> Here is a list of block layer and storage changes that have been discussed.  
> It
> is useful to have a roadmap of changes in order to avoid duplication, allow
> more developers to contribute, and to communicate the direction of storage in
> QEMU.
> 
> I suggest we first do a braindump of all changes that have been discussed.
> Later we can discuss specific changes and if/when they fit into the roadmap -
> please don't jump into discussion about specific changes yet.
> 
> Kevin: I hope this a useful starting point.  Here are all the items
> that I am aware of:
> 
> =Material for next QEMU release=
> 
> Coroutines in the block layer [Kevin]
>  * Programming model to simplify block drivers without blocking QEMU threads
> 
> Generic copy-on-read [Stefan]
>  * Populate image file to avoid fetching same block from backing file
> again later
> 
> Generic image streaming [Stefan]
>  * Make block_stream commands available for all image formats that
> support backing files
> 
> Live block copy [Marcelo/Kevin/Stefan?]
>  * Copy the contents of an image file while a guest is using it
> 
> In-place qcow2 <-> qed conversion [Devin, GSoC 2011]:
>  * Fast conversion between qcow2 and qed image formats without copy all data
> 
> VMDK enhancements [Fam, GSoC 2011]
>  * Implement latest VMDK specs to support modern image files
> 
> Block I/O limits [Zhi Yong]
>  * Resource control for guest I/O bandwidth/iops consumption

Another item that just came up on IRC again: Allow guests to toggle WCE,
so that we finally can get rid of the cache=writethrough default. We
should definitely get this done before 1.0.

Kevin