ACK: [{groovy, focal}:linux-azure][PATCH] PM: hibernate: Batch hibernate and resume IO requests

[Andrea Righi]

On Fri, Dec 11, 2020 at 04:52:28PM -0300, Marcelo Henrique Cerri wrote:
> From: Xiaoyi Chen <cxiaoyi at amazon.com>
> 
> BugLink: https://bugs.launchpad.net/bugs/1904458
> 
> Hibernate and resume process submits individual IO requests for each page
> of the data, so use blk_plug to improve the batching of these requests.
> 
> Testing this change with hibernate and resumes consistently shows merging
> of the IO requests and more than an order of magnitude improvement in
> hibernate and resume speed is observed.
> 
> One hibernate and resume cycle for 16GB RAM out of 32GB in use takes
> around 21 minutes before the change, and 1 minutes after the change on
> a system with limited storage IOPS.
> 
> Signed-off-by: Xiaoyi Chen <cxiaoyi at amazon.com>
> Co-Developed-by: Anchal Agarwal <anchalag at amazon.com>
> Signed-off-by: Anchal Agarwal <anchalag at amazon.com>
> [ rjw: Subject and changelog edits, white space damage fixes ]
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
> (cherry picked from commit 55c4478a8f0ecedc0c1a0c9379380249985c372a)
> Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri at canonical.com>
> ---

This has been applied already to linux-aws for the same reason, so it
makes sense to have it also in linux-azure. Therefore:

Acked-by: Andrea Righi <andrea.righi at canonical.com>