ACK: [SRU][G/aws][PATCH 0/2] aws: update patch to batch hibernate and resume IO requests
Stefan Bader
stefan.bader at canonical.com
Wed Nov 4 14:14:36 UTC 2020
On 04.11.20 13:05, Andrea Righi wrote:
> BugLink: https://bugs.launchpad.net/bugs/1902864
>
> [Impact]
>
> During hibernation and resume the kernel is submitting an individual IO
> request for each page of data. In the aws kernel we are using a custom
> SAUCE patch to batch IO requests together in order to achieve better
> performance.
>
> Recently a patch designed to achieve the same goal has been applied
> upstream. This patch has been acknowledged by Amazon and it has shown a
> performance improvement.
>
> Moreover, this patch looks much cleaner compared to the custom patch
> that we are using and it's upstream, so it makes sense to drop the
> previous patch and apply this new one.
>
> [Test case]
>
> Hibernate + resume and measure the time required to perform these
> operations.
>
> Performance result reported by Amazon:
>
> 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.
>
> [Fix]
>
> Apply the following upstream commit:
>
> 55c4478a8f0ecedc0c1a0c9379380249985c372a ("PM: hibernate: Batch hibernate and resume IO requests")
>
> Drop the custom aws SAUCE patch:
>
> 11c3fa3b29722124f5c9122671983614383686db ("UBUNTU: SAUCE: [aws] PM / hibernate: Speed up hibernation by batching requests")
>
> [Regression potential]
>
> Upstream patch that allows to drop a custom patch that is doing the same
> thing. The only potential regression would be a performance drop, but
> according to Amazon's tests and our tests, we didn't notice any
> performance regression. Any other kind of regression would be considered
> as upstream regressions.
>
> ----------------------------------------------------------------
> Andrea Righi (1):
> Revert "UBUNTU: SAUCE: [aws] PM / hibernate: Speed up hibernation by batching requests"
>
> Xiaoyi Chen (1):
> PM: hibernate: Batch hibernate and resume IO requests
>
> kernel/power/swap.c | 250 ++++++++++------------------------------------------
> 1 file changed, 49 insertions(+), 201 deletions(-)
>
>
Acked-by: Stefan Bader <stefan.bader at canonical.com>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
URL: <https://lists.ubuntu.com/archives/kernel-team/attachments/20201104/7b4c222f/attachment.sig>
More information about the kernel-team
mailing list