Hi Jeremy, Is this thing still on your list ? http://www.gossamer-threads.com/lists/linux/kernel/1281515 Ran powertop today, and events/0 and xenconsoled seem to be still responsible for the majority of wakeups. -- Sander _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Jeremy Fitzhardinge
2011-Mar-29 21:14 UTC
[Xen-devel] Re: events/0 and xenconsoled wakeups
On 03/25/2011 03:28 PM, Sander Eikelenboom wrote:> Hi Jeremy, > > Is this thing still on your list ? > http://www.gossamer-threads.com/lists/linux/kernel/1281515 > > Ran powertop today, and events/0 and xenconsoled seem to be still responsible for the majority of wakeups.Yeah. Unfortunately the underlying bug is a design error in the tty subsystem, which will be hard to fix. However, the one-liner fix can mitigate the problem and reduce the wakeups to 100Hz. Also, attaching a console to the various hvcs will also fix it. J _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Hello Jeremy, Tuesday, March 29, 2011, 11:14:04 PM, you wrote:> On 03/25/2011 03:28 PM, Sander Eikelenboom wrote: >> Hi Jeremy, >> >> Is this thing still on your list ? >> http://www.gossamer-threads.com/lists/linux/kernel/1281515 >> >> Ran powertop today, and events/0 and xenconsoled seem to be still responsible for the majority of wakeups.> Yeah. Unfortunately the underlying bug is a design error in the tty > subsystem, which will be hard to fix. However, the one-liner fix can > mitigate the problem and reduce the wakeups to 100Hz.> Also, attaching a console to the various hvcs will also fix it.Consoles of guests ? Could you give a example of how to do it ?> J-- Best regards, Sander mailto:linux@eikelenboom.it _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Jeremy Fitzhardinge
2011-Mar-31 17:34 UTC
[Xen-devel] Re: events/0 and xenconsoled wakeups
On 03/31/2011 05:19 AM, Sander Eikelenboom wrote:> Hello Jeremy, > > Tuesday, March 29, 2011, 11:14:04 PM, you wrote: > >> On 03/25/2011 03:28 PM, Sander Eikelenboom wrote: >>> Hi Jeremy, >>> >>> Is this thing still on your list ? >>> http://www.gossamer-threads.com/lists/linux/kernel/1281515 >>> >>> Ran powertop today, and events/0 and xenconsoled seem to be still responsible for the majority of wakeups. >> Yeah. Unfortunately the underlying bug is a design error in the tty >> subsystem, which will be hard to fix. However, the one-liner fix can >> mitigate the problem and reduce the wakeups to 100Hz. >> Also, attaching a console to the various hvcs will also fix it. > Consoles of guests ? > Could you give a example of how to do it ?Just running "xl console <domid>" will drain the pending console output, and stop all the wakeups. I think you can get xenconsoled to log into a file (or /dev/null) which will also fix it. The wakeups come from having unconsumed console output from the guest sitting in the pty buffer. J _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel