Re: [PATCH 0/5] Live Migration Acceleration with IAA Compression

[Juan Quintela <quintela@redhat.com>]

Yuan Liu <yuan1.liu@intel.com> wrote:
> Hi,
>
> I am writing to submit a code change aimed at enhancing live migration
> acceleration by leveraging the compression capability of the Intel
> In-Memory Analytics Accelerator (IAA).
>
> Enabling compression functionality during the live migration process can
> enhance performance, thereby reducing downtime and network bandwidth
> requirements. However, this improvement comes at the cost of additional
> CPU resources, posing a challenge for cloud service providers in terms of
> resource allocation. To address this challenge, I have focused on offloading
> the compression overhead to the IAA hardware, resulting in performance gains.
>
> The implementation of the IAA (de)compression code is based on Intel Query
> Processing Library (QPL), an open-source software project designed for
> IAA high-level software programming.
>
> Best regards,
> Yuan Liu

After reviewing the patches:

- why are you doing this on top of old compression code, that is
  obsolete, deprecated and buggy

- why are you not doing it on top of multifd.

You just need to add another compression method on top of multifd.
See how it was done for zstd:

commit 87dc6f5f665f581923536a1346220c7dcebe5105
Author: Juan Quintela <quintela@redhat.com>
Date:   Fri Dec 13 13:47:14 2019 +0100

    multifd: Add zstd compression multifd support
    
    Signed-off-by: Juan Quintela <quintela@redhat.com>
    Acked-by: Markus Armbruster <armbru@redhat.com>
    Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>


You will get 512KB buffers to compress, and it could be faster.
The way it is done today, every channel waits for its compression.  But
you could do a list of pending requests and be asynchronous there.

Later, Juan.