From mboxrd@z Thu Jan 1 00:00:00 1970 From: Erik Rull Subject: USB Transfer Rate with kvm-77 Date: Mon, 16 Mar 2009 19:53:45 +0100 Message-ID: <49BEA039.4090203@rdsoftware.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit To: kvm@vger.kernel.org Return-path: Received: from moutng.kundenserver.de ([212.227.126.171]:53857 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752422AbZCPSxr (ORCPT ); Mon, 16 Mar 2009 14:53:47 -0400 Sender: kvm-owner@vger.kernel.org List-ID: Hello, I'm currently testing Windows XP in a Linux host. I works well except the USB transfer rate. Printers and USB Pen Drives can be connected and get detected (I added host:auto...). My System only supports USB 1.1, the transfer rate in plain linux is okay. In the Guest Windows, the transfer rate is horribly slow! The transfer rate is ~ 2MB per Minute! This is far below the slowest defined USB transfer rates (1,5MBit / sec!). The system is nearly idle (in linux and windows) during the transfer. What could be the reason for that? I tested it also on a USB 2.0 system, same effect, but additionally the printers cause bluescreens within Windows :-) I need some ideas where to start investigating. I tested several USB Pen Drives (USB 2.0 capable), a USB DVD ROM Drive and two printers of different manufacturers (HP, Canon). All at the same transfer rate :-( It seems that there is a performance gap - but where? Thanks a lot! Best regards, Erik