From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:44904) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UPcaL-0004ua-En for qemu-devel@nongnu.org; Tue, 09 Apr 2013 13:43:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UPcaJ-0006kr-19 for qemu-devel@nongnu.org; Tue, 09 Apr 2013 13:43:57 -0400 Received: from e9.ny.us.ibm.com ([32.97.182.139]:49821) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UPcaI-0006kl-Sj for qemu-devel@nongnu.org; Tue, 09 Apr 2013 13:43:54 -0400 Received: from /spool/local by e9.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 9 Apr 2013 13:43:53 -0400 Received: from d01relay07.pok.ibm.com (d01relay07.pok.ibm.com [9.56.227.147]) by d01dlp02.pok.ibm.com (Postfix) with ESMTP id 349866E8048 for ; Tue, 9 Apr 2013 13:43:32 -0400 (EDT) Received: from d01av03.pok.ibm.com (d01av03.pok.ibm.com [9.56.224.217]) by d01relay07.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r39HhXaL46792924 for ; Tue, 9 Apr 2013 13:43:34 -0400 Received: from d01av03.pok.ibm.com (loopback [127.0.0.1]) by d01av03.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r39HhXHC005459 for ; Tue, 9 Apr 2013 14:43:33 -0300 Received: from [172.16.1.222] (klinux.watson.ibm.com [9.2.208.21]) by d01av03.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id r39HhXB7005400 for ; Tue, 9 Apr 2013 14:43:33 -0300 Message-ID: <51645345.60005@linux.vnet.ibm.com> Date: Tue, 09 Apr 2013 13:43:33 -0400 From: "Michael R. Hines" MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="------------020206030008030101000305" Subject: [Qemu-devel] latest master: major slowdown (something spinning?) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "qemu-devel@nongnu.org" This is a multi-part message in MIME format. --------------020206030008030101000305 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit *Here's the commit that causes the problem:* $ git checkout d185c094b404b4ff392b77d1244c0233da7d53bd qemu-char: eliminate busy waiting on can_read returning zero *Symptoms:* When the VM boots everything crawls and the host CPU is at 100%, messages are printing extremely slowly on the VM console and the VM is not making any boot progress......... printing kernel messages once a second or so....... Something in QEMU appears to be spinning. Here's my command line: qemu-system-x86_64 -enable-kvm -m 2048 -smp 2,sockets=1,cores=1,threads=1 -nodefconfig -rtc base=utc -no-shutdown disk.img -serial pty -monitor unix:/tmp/devguest,server,nowait -netdev type=tap,vhost=on,id=hostnet0,script=kvmifup.sh,downscript=kvmifdown.sh -device virtio-net-pci,netdev=hostnet0,mac=12:34:36:00:00:02 -usb -device usb-tablet,id=input0 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 - Michael Hines --------------020206030008030101000305 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Here's the commit that causes the problem:

$ git checkout d185c094b404b4ff392b77d1244c0233da7d53bd
qemu-char: eliminate busy waiting on can_read returning zero

Symptoms:

When the VM boots everything crawls and the host CPU is at 100%,
messages are printing extremely slowly on the VM console
and the VM is not making any boot progress......... printing kernel
messages once a second or so.......

Something in QEMU appears to be spinning.

Here's my command line:

qemu-system-x86_64 -enable-kvm -m 2048 -smp 2,sockets=1,cores=1,threads=1 -nodefconfig -rtc base=utc -no-shutdown disk.img -serial pty -monitor unix:/tmp/devguest,server,nowait -netdev type=tap,vhost=on,id=hostnet0,script=kvmifup.sh,downscript=kvmifdown.sh -device virtio-net-pci,netdev=hostnet0,mac=12:34:36:00:00:02 -usb -device usb-tablet,id=input0  -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5

- Michael Hines
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