[dm-devel] [PATCH] staging: writeboost: Add dm-writeboost

[Joe Thornber]

On Wed, Dec 10, 2014 at 08:00:13PM +0900, Akira Hayakawa wrote:
> Hi, Joe
> 
> Thanks for continuous evaluation.

Some more details:

dd, with block size 512b
------------------------

raw spindle      : 143
writeboost Type 0: 137
writeboost Type 1: 130

dd, with block size 4k
----------------------

raw spindle      : 31
writeboost Type 0: 29
writeboost Type 1: 81


dd, with block size 64m
-----------------------

raw spindle      : 8.9
writeboost Type 0: 32
writeboost Type 1: 72



So maybe it's just volume of IO that's causing the problem?  What's
the difference between Type 0 and Type 1?  In the code I notice you
have 'rambuf' structures, are you caching IO in memory?