From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: Interrupt forwarding Date: Mon, 14 Mar 2005 22:59:59 +0100 Message-ID: References: <9e473391050312100257800c81@mail.gmail.com> <200503121812.59154.maw48@cl.cam.ac.uk> <200503141544.21351.maw48@cl.cam.ac.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <200503141544.21351.maw48@cl.cam.ac.uk> (Mark Williamson's message of "Mon, 14 Mar 2005 15:44:21 +0000") Sender: xen-devel-admin@lists.sourceforge.net Errors-To: xen-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Mark Williamson Cc: Mark Williamson , xen-devel@lists.sourceforge.net, Jon Smirl List-Id: xen-devel@lists.xenproject.org Mark Williamson writes: > > I'd seen they're available on some non-PCIE hardware. I assumed it was just > recent / high end hardware (maybe just on PCI-X). (for instance, I think my > workstation at Intel does use MSI interrupts and IIRC has PCI / PCI-X > support). > > Does anyone know to what extent MSI is actually used these days? Not very widely. The PCI card and the chipset has to support it. Most PCI cards don't. Non Intel chipsets often don't support MSI at all (e.g. on most AMD systems). Worst there are even some cards who advertise MSI support, but they lock up when you actually use it. PCI-Express requires MSI support though, but there are hardly any PCI-Express cards already available. MSI-X support is even worse, only a few highend cards seem to support it. Also the MSI support in Linux seems to be not entirely stable yet. -Andi ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click