From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Vrabel Subject: Re: [PATCH 11/11] libxl, xl: add event_channels option to xl configuration file Date: Mon, 14 Oct 2013 17:43:15 +0100 Message-ID: <525C1F23.1050807@citrix.com> References: <1380731760-2749-1-git-send-email-david.vrabel@citrix.com> <1380731760-2749-12-git-send-email-david.vrabel@citrix.com> <21084.63.574310.816920@mariner.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <21084.63.574310.816920@mariner.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Jackson Cc: Keir Fraser , Ian Campbell , Jan Beulich , xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 14/10/13 15:31, Ian Jackson wrote: > David Vrabel writes ("[PATCH 11/11] libxl,xl: add event_channels option to xl configuration file"): >> +=item B >> + >> +Limit the guest to using at most N event channels (PV interrupts). >> +Guests use hypervisor resources for each event channel they use. >> + >> +The default of 1023 should be sufficient for typical guests. The >> +maximum 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). > > It's not clear to me what happens if you specify a larger value for > max_event_channels than the guest and/or hypervisor support. The guest is limited to the minimum of: - what it supports - what the hypervisor support - what max_event_channels is set to. The docs should be clarified to say this. David