From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <dvrabel@cantab.net>
Subject: Re: [PATCH 11/11] libxl,
 xl: add event_channels option to xl configuration file
Date: Tue, 01 Oct 2013 13:53:58 +0100
Message-ID: <524AC5E6.7040007@cantab.net>
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To: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Keir Fraser <keir@xen.org>, Ian Jackson <ian.jackson@eu.citrix.com>, David Vrabel <david.vrabel@citrix.com>, Jan Beulich <jbeulich@suse.com>, xen-devel@lists.xen.org
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On 01/10/13 13:36, Ian Campbell wrote:
> On Fri, 2013-09-27 at 11:55 +0100, David Vrabel wrote:
> 
>> +value depends what the guest supports.  Guests supporting the
>> +FIFO-based event channel ABI support up to 131,071 event channels.
>> +Other guests are limited to 4095 (64-bit x86 and ARM) or 1023 (32-bit
>> +x86).
> 
> Does this setting really restrict the classical ABI to 127? TBH I'm fine
> if it does, just curious.

Yes, the limit applies regardless of the ABI that a guest uses.

With the 2-level ABI it doesn't save much Xen resources though (1 xen
heap page per 128 events).

David