Re: [dm-devel] [Lsf-pc] [Topic] Bcache

[chetan loke <loke chetan gmail com>]

On Wed, Mar 14, 2012 at 11:53 AM, Vivek Goyal <vgoyal redhat com> wrote:
> On Wed, Mar 14, 2012 at 09:32:28AM -0400, Kent Overstreet wrote:
>> I'm already registered to attend, but would it be too late in the
>> process to give a talk? I'd like to give a short talk about bcache, what
>> it does and where it's going (more than just caching).
>
> [CCing dm-devel list]
>
> I am curious if you considered writing a device mapper driver for this? If
> yes, why that is not a good choice. It seems to be stacked device and device
> mapper should be good at that. All the configuration through sysfs seems
> little odd to me.

I'm not a dm guru but a quick scan at flash-cache seems like it does
what you are saying. Now, if performance isn't acceptable then hashes
can be replaced with trees and what-not. Also no one would need to
re-invent the stacking mechanism. I saw thin support(atleast
documented) for dm. Plus, no matter what cache you come up with you
may have to persist/store the meta-data associated with it. And dm
seems like the right place to abstract that.



> Vivek

Chetan