Chris Birkinshaw
2008-Feb-14 10:07 UTC
[Xen-devel] CONFIG_PREEMPT_RT=y possible in Dom0 kernel?
HI, Is it possible to specify CONFIG_PREEMPT_RT=y in the Dom0 kernel? It seems that it is forbidden as it is not a menu option in make menuconfig and gets removed if I manually add it to the .config. I want to run a sound server on Dom0 and am having problems with xruns at present, so need to be able to run a preemptive kernel. Thanks, Chris _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2008-Feb-14 10:09 UTC
Re: [Xen-devel] CONFIG_PREEMPT_RT=y possible in Dom0 kernel?
No, involuntary preemption isn¹t supported. -- Keir On 14/2/08 10:07, "Chris Birkinshaw" <chris.birkinshaw@googlemail.com> wrote:> > > HI, > > Is it possible to specify CONFIG_PREEMPT_RT=y in the Dom0 kernel? It seems > that it is forbidden as it is not a menu option in make menuconfig and gets > removed if I manually add it to the .config. > > I want to run a sound server on Dom0 and am having problems with xruns at > present, so need to be able to run a preemptive kernel. > > Thanks, > > Chris > > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Chris Birkinshaw
2008-Feb-14 10:13 UTC
Re: [Xen-devel] CONFIG_PREEMPT_RT=y possible in Dom0 kernel?
Is there any workaround or alternative approach which will solve my problem? Many thanks, Chris On Thu, Feb 14, 2008 at 10:09 AM, Keir Fraser <Keir.Fraser@cl.cam.ac.uk> wrote:> No, involuntary preemption isn''t supported. > > -- Keir > > > On 14/2/08 10:07, "Chris Birkinshaw" <chris.birkinshaw@googlemail.com> > wrote: > > > > HI, > > Is it possible to specify CONFIG_PREEMPT_RT=y in the Dom0 kernel? It seems > that it is forbidden as it is not a menu option in make menuconfig and gets > removed if I manually add it to the .config. > > I want to run a sound server on Dom0 and am having problems with xruns at > present, so need to be able to run a preemptive kernel. > > Thanks, > > Chris > > > ------------------------------ > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel > > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2008-Feb-14 10:28 UTC
Re: [Xen-devel] CONFIG_PREEMPT_RT=y possible in Dom0 kernel?
Pin dom0 to its own CPU? If the xruns are occurring because of competing load in dom0 itself, or you have a SMP dom0 and don¹t want to pin all its VCPUs, you could pull your sound server out into another domain and pin that instead. Either way, the VCPU pinning is ensuring that your sound server is not impacted by the Linux or Xen schedulers. The cost is that you burn a core or hyperthread on your sound server. -- Keir On 14/2/08 10:13, "Chris Birkinshaw" <chris.birkinshaw@googlemail.com> wrote:> Is there any workaround or alternative approach which will solve my problem? > > Many thanks, > > Chris > > > > On Thu, Feb 14, 2008 at 10:09 AM, Keir Fraser <Keir.Fraser@cl.cam.ac.uk> > wrote: >> No, involuntary preemption isn''t supported. >> >> -- Keir >> >> >> On 14/2/08 10:07, "Chris Birkinshaw" <chris.birkinshaw@googlemail.com> wrote: >> >>> >>> >>> HI, >>> >>> Is it possible to specify CONFIG_PREEMPT_RT=y in the Dom0 kernel? It seems >>> that it is forbidden as it is not a menu option in make menuconfig and gets >>> removed if I manually add it to the .config. >>> >>> I want to run a sound server on Dom0 and am having problems with xruns at >>> present, so need to be able to run a preemptive kernel. >>> >>> Thanks, >>> >>> Chris >>> >>> >>> >>> _______________________________________________ >>> Xen-devel mailing list >>> Xen-devel@lists.xensource.com >>> http://lists.xensource.com/xen-devel >> > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel