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RE: [Xen-devel] XCP: dom0 scalability

> At 00:16 +0100 on 13 Oct (1286928975), Jeremy Fitzhardinge wrote:
> > I'm a big fan of disaggregation, but from a performance perspective
> > xenstored seems pretty insignificant.
> True, xenstored is more a victim of dom0 load than a cause of it.
> We've
> seen some pretty nasty performance when trying to boot lots of VMs with
> a loaded dom0; PV drivers in the VMs could block for many seconds
> waiting for xenstore to get back to them.  It still makes sense to get
> it out of there.

Hmmm... if dom0 is getting scheduled enough and the VMs are still
blocking on xenstore (i.e. the Linux scheduler in dom0 is the problem),
getting xenstore off of dom0 makes sense.  But if the reason xenstore
is not getting back to them is because dom0 is simply not getting
enough cpu time (i.e. the Xen scheduler is the problem), moving xenstore
out of there may not only NOT help, but may make things worse.  True?

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