[dm-devel] [PATCH 0/2] dm-zoned: improve cache performance

[Damien Le Moal]

On 2020/05/13 16:07, Hannes Reinecke wrote:
> Hi all,
> 
> here are two patches to improve performance when a regular device
> is specified for dm-zoned.
> Damien noted that we have a performance drop after the zones on the
> regular device are used up, as then the random zones on the zoned
> device are being used, _and_ reclaim is running on the same disk.
> This slows down I/O whle using random zones, increasing again after
> the random zones are used up.
> This patchset fixes this by not allowing random zones for caching
> if a regular device is present.

Awesome ! I will run this overnight to see how it compares with the previous
results I sent.

And I need to send something to fix the setup warning I am seeing, but that is a
block or scsi patch I think. Had no time to dig.

> 
> Patch is relative to the dm-5.8 branch from
> git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git
> 
> As usual, comments and reviews are welcome.
> 
> 
> Hannes Reinecke (2):
>   dm-zoned: invert zone check in dmz_reset_zone()
>   dm-zoned: split off random and cache zones
> 
>  .../admin-guide/device-mapper/dm-zoned.rst    |  17 +-
>  drivers/md/dm-zoned-metadata.c                | 157 +++++++++++++-----
>  drivers/md/dm-zoned-reclaim.c                 |  70 ++++----
>  drivers/md/dm-zoned-target.c                  |  19 ++-
>  drivers/md/dm-zoned.h                         |   7 +-
>  5 files changed, 189 insertions(+), 81 deletions(-)
> 


-- 
Damien Le Moal
Western Digital Research