Re: [PATCH] dm writecache: fix inaccurate reads/writes stats

[Mikulas Patocka]

On Wed, 6 Jul 2022, Yu Kuai wrote:

> From: Yu Kuai <yukuai3@xxxxxxxxxx>
> 
> Test procedures:
> 
> 1) format a dm writecache device with 4k blocksize.
> 2) flush cache.
> 3) cache 1G data through write.
> 4) clear stats.
> 5) read 2G data with bs=1m.
> 6) read stats.
> 
> Expected result:
> cache hit ratio is 50%.
> 
> Test result:
> stats: 0, 1011345, 749201, 0, 263168, 262144, 0, 0, 0, 0, 0, 0, 0, 0
> ratio is 99% (262144/263168)

Hi

Here I'm providing patches that change the dm-writecache counting from 
requests to blocks.

Mike, you can queue them for the next merge window.

Mikulas