Re: [GIT] Bcache version 12

On Mon, Sep 19, 2011 at 10:28:03AM +0300, Pekka Enberg wrote:

Hi Kent,

On Sat, Sep 10, 2011 at 9:45 AM, Kent Overstreet
[off-list ref] wrote:

quoted

bcache, n.: a cache for arbitrary block devices that uses an SSD

It's probably past time I started poking people to see about getting
this stuff in. It's synced up with mainline, the documentation is for
once relatively up to date, and it looks just about production ready.

Suggestions are more than welcome on how to make it easier to review -
it's entirely too much code, I know (near 10k lines now). I'll be
emailing the patches that touch other parts of the kernel separately.

Short overview:
Bcache does both writethrough and writeback caching. It presents itself
as a new block device, a bit like say md. You can cache an arbitrary
number of block devices with a single cache device, and attach and
detach things at runtime - it's quite flexible.

The changelog is pretty useless for people like myself who have never
heard of bcache before because it lacks any explanation why bcache is
useful (i.e. a real-world use case).

                        Pekka

Well, I think you'll want the documentation for that -
Documentation/bcache.txt is somewhat up to date and should answer that
decently.

Short version: bcache is for making IO faster.