From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: USB Passthrough 1.1 performance problem... Date: Tue, 14 Dec 2010 00:27:36 +0100 Message-ID: <4D06ABE8.3050908@web.de> References: <4D04B645.3010100@brakkee.org> <4D0537A8.8000607@brakkee.org> <4D0549AA.2020007@web.de> <4D054D37.7040107@brakkee.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigD55BAB032B2E75B6A809AD0C" Cc: kvm@vger.kernel.org To: Erik Brakkee Return-path: Received: from fmmailgate02.web.de ([217.72.192.227]:34725 "EHLO fmmailgate02.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752076Ab0LMX1l (ORCPT ); Mon, 13 Dec 2010 18:27:41 -0500 In-Reply-To: <4D054D37.7040107@brakkee.org> Sender: kvm-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigD55BAB032B2E75B6A809AD0C Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Am 12.12.2010 23:31, Erik Brakkee wrote: > Jan Kiszka wrote: >> >>>> Are there some tuning parameters I can use or perhaps even kernel >>>> configuration paramters on the host to solve this? >>>> >>>> Cheers >>>> Erik >>>> >>>> Host: Motherboard Supermicro X8DTi-F, Intel Xeon L5630, 12MB >>>> OS: Opensuse 11.3 64 bit >>>> >>>> Guest: OS: Opensuse 11.3 64 bit >>>> =20 >>> I can say now that I am giving up on getting this to work. One >>> alternative was to use PCI passthrough the USB hardware, but that >>> didn't work for the USB that was on the motherboard. So I bought a US= B >>> PCI card and tried to use PCI passthrough for that. Unfortunately oth= er >>> problems occured there. >>> >>> For one, the problem with 4K alignment. But I could fix that by using= >>> the pci=3Dresource_alignment=3D... kernel parameter. In my grub/menu.= lst it >>> says: >>> >>> kernel /vmlinuz-2.6.34.7-0.5-default root=3D/dev/hsystem/root qui= et >>> showopts intel_iommu=3Don >>> pci=3Dresource_alignment=3D01:04.0;01:04.1;01:04.2 noirqdebug vga= =3D0x31a >>> >>> >>> The noirqdebug flas was needed to avoid the host from disabling the I= RQ >>> (it was a shared IRQ). >>> >>> Using this, I could configure PCI passthrough and start the VM. Also = the >>> USB device showed up there. Only it did not work at all. >>> >>> Here is a summary of my journey up until know: >>> >>> The original approach I wanted to use was to pass my old PCI card (Wi= nTV >>> PVR-500) to a VM. This card is a well supported card and has been doi= ng >>> fine for me. Because of the PCI passthrough problems with the wintv >>> card, I decided to try a USB card instead. This gave me a 'ctrl buffe= r >>> too small' issue that I could solve by taking the source RPM for kvm = and >>> applying a known patch from red hat (increasing buffer size from 2048= to >>> 8192). But then I got jerky video, probably due to USB 1.1 issues. To= >>> bypass these I could use PCI passthrough for USB. But with the PCI >>> passthrough of this card I am again running into issues probably rela= ted >>> to Shared IRQs. So, after all this I am back to square one. >>> >>> I have now modified my approach so instead of running a separate mini= mal >>> host with my old server as a guest, I am now running the old server >>> (same install) on the new hardware, using it as a host. I would >>> definitely be interested in trying this out further in the future. I >>> even tried Xen for a brief moment, only to realize that my host and >>> guest felt slower (slower startup and execution) and much more diffic= ult >>> to handle. >>> >>> From the experience of the last two days fulltime trying to get thin= gs >>> working I can only conclude that the following two features would be >>> really important to have: >>> >>> * Extended PCI passthrough support >>> o shared IRQ support >>> =20 >> Addressed by the series I sent out today. >> =20 > Does this mean I have a chance now that PCI passthrough of my WinTV > PVR-500 might work now? > What version is this and where can I get this for opensuse? Currently you have to clone my git trees [1, 2], then build and install those to have the feature. Will take a while to see it in releases, and after that also Opensuse packages. Jan [1] git://git.kiszka.org/linux-kvm.git queues/dev-assign [2] git://git.kiszka.org/qemu-kvm.git queues/dev-assign --------------enigD55BAB032B2E75B6A809AD0C Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org/ iEYEARECAAYFAk0Gq+gACgkQitSsb3rl5xQCUgCgjwDAtNQ0giUf5iPDnteOTNqP f0sAn0I/lQ3eGtwhfrCy10dcwRuWuCuS =j1qE -----END PGP SIGNATURE----- --------------enigD55BAB032B2E75B6A809AD0C--