[dm-devel] Re: Too many I/O controller patches

[Andrea Righi <righi andrea gmail com>]

Balbir Singh wrote:
> Dave Hansen wrote:
>> On Mon, 2008-08-04 at 17:51 +0900, Ryo Tsuruta wrote:
>>> This series of patches of dm-ioband now includes "The bio tracking mechanism,"
>>> which has been posted individually to this mailing list.
>>> This makes it easy for anybody to control the I/O bandwidth even when
>>> the I/O is one of delayed-write requests.
>> During the Containers mini-summit at OLS, it was mentioned that there
>> are at least *FOUR* of these I/O controllers floating around.  Have you
>> talked to the other authors?  (I've cc'd at least one of them).
>>
>> We obviously can't come to any kind of real consensus with people just
>> tossing the same patches back and forth.
> 
> Ryo and Andrea - Naveen and Satoshi met up at OLS and discussed their approach.
> It would be really nice to see an RFC, I know Andrea did work on this and
> compared the approaches.
> 

yes, I wrote down something about the comparison of priority-based vs
bandwidth shaping solutions in terms of performance predictability.  And
other considerations, like the one I cited before, about dirty-ratio
throttling in memory, AIO handling, etc.

Something is also reported in the io-throttle documentation:

http://marc.info/?l=linux-kernel&m=121780176907686&w=2

But ok, I agree with Balbir, I can try to put the things together (in a
better form in particular) and try to post an RFC together with Ryo.

Ryo, do you have other documentation besides the info reported in the
dm-ioband website?

Thanks,
-Andrea