[CRIU] Criu Page server on source

[Adrian Reber]

On Thu, Apr 01, 2021 at 04:08:33PM +0100, DALLEL KHEZZANE wrote:
>  Hello ,
> 
> on the Documentation this figure, Criu-memory-wflow.png
> <https://criu.org/w/images/3/39/Criu-memory-wflow.png> (attached below)
> showcasing the memory transfer workflow in each of these cases:
> - classic flow
> - page server on destination
> - page server on source
> - lazy migration
> I tried these scenarios to compare downtime, but in the case of page server
> on source it is shown on the figure  that it can be done without writing to
> disk at all.correct me if i misunderstood.

This sounds strange. Why do you start the page server on the source side
of the migration? The page server should be running on the destination
side. This way it is possible for CRIU to directly transfer the memory
pages over the network to the destination without writing the pages
locally to disk.

> after lauching page server on source then performing checkpoint with page
> server on source,
> how can i transfer the image pages in order to restore on destination
> without writing to disk?
> i don't understand this particular page-server on source workflow on the
> figure what does the arrow with remote stand for?

This sounds like a misunderstanding. The page server should run on the
destination side of the migration.

		Adrian