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Re: [Xen-devel] increase evtchn limits

To: Mukesh Rathor <mukesh.rathor@xxxxxxxxxx>, "Xen-devel@xxxxxxxxxxxxxxxxxxx" <Xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] increase evtchn limits
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Fri, 21 May 2010 08:01:38 +0100
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On 21/05/2010 04:41, "Mukesh Rathor" <mukesh.rathor@xxxxxxxxxx> wrote:

> I'm trying to boot up with lot more than 32 vcpus on this very large box.
> I overcame vcpu_info[MAX_VIRT_CPUS] by doing vcpu placement hypercall
> in guest, but now running into evt channel limit (lots of devices):
>        unsigned long evtchn_pending[sizeof(unsigned long) * 8];
> which limits to 512 max for my 64bit dom0.

How many CPUs do you have to bring up? How many event channels are we
squandering per CPU in PV Linux right now (can you enumerate them)?

 -- Keir

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