From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: increase evtchn limits
Date: Fri, 21 May 2010 08:12:13 +0100
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To: Zhigang Wang <zhigang.x.wang@oracle.com>, Mukesh Rathor <mukesh.rathor@oracle.com>
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On 21/05/2010 06:07, "Zhigang Wang" <zhigang.x.wang@oracle.com> wrote:

>>        unsigned long evtchn_pending[sizeof(unsigned long) * 8];
>> 
> I'm not sure, but it seems: 1024 for 32bit and 4096 for 64bit.
> 
> 32bit: 4 * (4 * 8) * 8 = 1024
> 64bit: 8 * (8 * 8) * 8 = 4096

This is correct. Which is why I wonder how many CPUs you are dealing with,
and how many event channels are being allocated per CPU. 4096 event channels
ought to be plenty for dom0 bringup on even a very big system.

 K.