Re: [PATCH v6 00/12] Use Intel DSA accelerator to offload zero page checking in multifd live migration.

["Dr. David Alan Gilbert" <dave@treblig.org>]

* Peter Xu (peterx@redhat.com) wrote:

> The doc update is still missing under docs/, we may need that for a final
> merge.
> 
> Are you using this in production?  How it performs in real life?  What is
> the major issue to solve for you?  Is it "zero detect eats cpu too much",
> or "migration too slow", or "we're doing experiment with the new hardwares,
> and see how it goes if we apply it on top of migrations"?
> 
> There're a lot of new code added for dsa just for this optimization on zero
> page detection.  We'd better understand the major benefits, and also
> whether that's applicable to other part of qemu or migration-only.  I
> actually wonder if we're going to support enqcmd whether migration is the
> best starting point (rather than other places where we emulate tons of
> devices, and maybe some backends can speedup IOs with enqcmd in some
> form?).. but it's more of a pure question.

The other thing that worries me here is that there's not much abstraction,
I'm sure there's a whole bunch of offload cards that could do tricks like
this; how do we avoid having this much extra code for each one?

Dave

> 
> Thanks,
> 
> -- 
> Peter Xu
> 
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