Pasi Kärkkäinen
2010-Jan-13 20:36 UTC
[Xen-devel] Xen hypervisor dom0_vcpus option broken in Xen 3.4 ?
Hello, while discussing things on xen-users we noticed this: (XEN) Xen version 3.4.2 (root@(none)) (gcc version 4.4.2 20091027 (RedHat 4.4.2-7) (GCC) ) Mon Dec 14 06:53:18 EET 2009 (XEN) Latest ChangeSet: unavailable (XEN) Command line: dom0_mem=1G loglvl=all guest_loglvl=all com1=38400,8n1 console=com1 dom0_vcpus=1 .. (XEN) Dom0 has maximum 4 VCPUs .. Has dom0_vcpus option name changed, or is it just broken? -- Pasi _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Andrew Lyon
2010-Jan-13 21:38 UTC
Re: [Xen-devel] Xen hypervisor dom0_vcpus option broken in Xen 3.4 ?
On Wed, Jan 13, 2010 at 8:36 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote:> Hello, > > while discussing things on xen-users we noticed this: > > (XEN) Xen version 3.4.2 (root@(none)) (gcc version 4.4.2 20091027 (RedHat 4.4.2-7) (GCC) ) Mon Dec 14 06:53:18 EET 2009 > (XEN) Latest ChangeSet: unavailable > (XEN) Command line: dom0_mem=1G loglvl=all guest_loglvl=all com1=38400,8n1 console=com1 dom0_vcpus=1 > .. > (XEN) Dom0 has maximum 4 VCPUs > .. > > Has dom0_vcpus option name changed, or is it just broken? > > -- Pasi > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel >Looks like it is called dom0_max_vcpus in 3.4.2: cat xen-3.4.2.gz |gzip -d | strings | grep cpus | grep dom0 dom0_vcpus_pin dom0_max_vcpus Andy _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Andrew Lyon
2010-Jan-13 21:47 UTC
Re: [Xen-devel] Xen hypervisor dom0_vcpus option broken in Xen 3.4 ?
On Wed, Jan 13, 2010 at 9:38 PM, Andrew Lyon <andrew.lyon@gmail.com> wrote:> On Wed, Jan 13, 2010 at 8:36 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote: >> Hello, >> >> while discussing things on xen-users we noticed this: >> >> (XEN) Xen version 3.4.2 (root@(none)) (gcc version 4.4.2 20091027 (RedHat 4.4.2-7) (GCC) ) Mon Dec 14 06:53:18 EET 2009 >> (XEN) Latest ChangeSet: unavailable >> (XEN) Command line: dom0_mem=1G loglvl=all guest_loglvl=all com1=38400,8n1 console=com1 dom0_vcpus=1 >> .. >> (XEN) Dom0 has maximum 4 VCPUs >> .. >> >> Has dom0_vcpus option name changed, or is it just broken? >> >> -- Pasi >> >> >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.xensource.com >> http://lists.xensource.com/xen-devel >> > > Looks like it is called dom0_max_vcpus in 3.4.2: > > cat xen-3.4.2.gz |gzip -d | strings | grep cpus | grep dom0 > dom0_vcpus_pin > dom0_max_vcpus > > Andy >Also see this thread http://article.gmane.org/gmane.comp.emulators.xen.devel/69017, which seems to suggest that dom0_max_vcpus is parameter for the Xen hypervisor (xen.gz) itself, while dom0_vcpus is for the dom0 kernel and causes it to hot-unplug the "extra" cpu''s so that they can be (re)added later. I believe the xen 2.6.18 kernel also supports booting pv domUs with more max-cpus than active at startup, again so that they can be added later. I guess dom0_vcpus only works with Xen 2.6.18, I can find no trace of it in the openSUSE Xen kernel source. Andy _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Pasi Kärkkäinen
2010-Jan-13 21:48 UTC
Re: [Xen-devel] Xen hypervisor dom0_vcpus option broken in Xen 3.4 ?
On Wed, Jan 13, 2010 at 09:38:56PM +0000, Andrew Lyon wrote:> On Wed, Jan 13, 2010 at 8:36 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote: > > Hello, > > > > while discussing things on xen-users we noticed this: > > > > (XEN) Xen version 3.4.2 (root@(none)) (gcc version 4.4.2 20091027 (RedHat 4.4.2-7) (GCC) ) Mon Dec 14 06:53:18 EET 2009 > > (XEN) Latest ChangeSet: unavailable > > (XEN) Command line: dom0_mem=1G loglvl=all guest_loglvl=all com1=38400,8n1 console=com1 dom0_vcpus=1 > > .. > > (XEN) Dom0 has maximum 4 VCPUs > > .. > > > > Has dom0_vcpus option name changed, or is it just broken? > > > > -- Pasi > > > > > > _______________________________________________ > > Xen-devel mailing list > > Xen-devel@lists.xensource.com > > http://lists.xensource.com/xen-devel > > > > Looks like it is called dom0_max_vcpus in 3.4.2: > > cat xen-3.4.2.gz |gzip -d | strings | grep cpus | grep dom0 > dom0_vcpus_pin > dom0_max_vcpus >Good catch! And good timing, I was just about to start digging the source :) Thanks! -- Pasi _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Pasi Kärkkäinen
2010-Jan-13 21:52 UTC
Re: [Xen-devel] Xen hypervisor dom0_vcpus option broken in Xen 3.4 ?
On Wed, Jan 13, 2010 at 09:47:38PM +0000, Andrew Lyon wrote:> On Wed, Jan 13, 2010 at 9:38 PM, Andrew Lyon <andrew.lyon@gmail.com> wrote: > > On Wed, Jan 13, 2010 at 8:36 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote: > >> Hello, > >> > >> while discussing things on xen-users we noticed this: > >> > >> (XEN) Xen version 3.4.2 (root@(none)) (gcc version 4.4.2 20091027 (RedHat 4.4.2-7) (GCC) ) Mon Dec 14 06:53:18 EET 2009 > >> (XEN) Latest ChangeSet: unavailable > >> (XEN) Command line: dom0_mem=1G loglvl=all guest_loglvl=all com1=38400,8n1 console=com1 dom0_vcpus=1 > >> .. > >> (XEN) Dom0 has maximum 4 VCPUs > >> .. > >> > >> Has dom0_vcpus option name changed, or is it just broken? > >> > >> -- Pasi > >> > >> > >> _______________________________________________ > >> Xen-devel mailing list > >> Xen-devel@lists.xensource.com > >> http://lists.xensource.com/xen-devel > >> > > > > Looks like it is called dom0_max_vcpus in 3.4.2: > > > > cat xen-3.4.2.gz |gzip -d | strings | grep cpus | grep dom0 > > dom0_vcpus_pin > > dom0_max_vcpus > > > > Andy > > > > Also see this thread > http://article.gmane.org/gmane.comp.emulators.xen.devel/69017, which > seems to suggest that dom0_max_vcpus is parameter for the Xen > hypervisor (xen.gz) itself, while dom0_vcpus is for the dom0 kernel > and causes it to hot-unplug the "extra" cpu''s so that they can be > (re)added later. > > I believe the xen 2.6.18 kernel also supports booting pv domUs with > more max-cpus than active at startup, again so that they can be added > later. > > I guess dom0_vcpus only works with Xen 2.6.18, I can find no trace of > it in the openSUSE Xen kernel source. >I''ve been using dom0_vcpus for Xen *hypervisor* with RHEL5/CentOS5 (which includes Xen 3.1.2.) I think you mixed that up with xend-config.sxp dom0-cpus option, which is totally different thing, like Keir explains in that thread. But yeah, maybe now I remember it''s called dom0_max_vcpus nowadays. Thanks. -- Pasi _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Andrew Lyon
2010-Jan-13 21:54 UTC
Re: [Xen-devel] Xen hypervisor dom0_vcpus option broken in Xen 3.4 ?
On Wed, Jan 13, 2010 at 9:52 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote:> On Wed, Jan 13, 2010 at 09:47:38PM +0000, Andrew Lyon wrote: >> On Wed, Jan 13, 2010 at 9:38 PM, Andrew Lyon <andrew.lyon@gmail.com> wrote: >> > On Wed, Jan 13, 2010 at 8:36 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote: >> >> Hello, >> >> >> >> while discussing things on xen-users we noticed this: >> >> >> >> (XEN) Xen version 3.4.2 (root@(none)) (gcc version 4.4.2 20091027 (RedHat 4.4.2-7) (GCC) ) Mon Dec 14 06:53:18 EET 2009 >> >> (XEN) Latest ChangeSet: unavailable >> >> (XEN) Command line: dom0_mem=1G loglvl=all guest_loglvl=all com1=38400,8n1 console=com1 dom0_vcpus=1 >> >> .. >> >> (XEN) Dom0 has maximum 4 VCPUs >> >> .. >> >> >> >> Has dom0_vcpus option name changed, or is it just broken? >> >> >> >> -- Pasi >> >> >> >> >> >> _______________________________________________ >> >> Xen-devel mailing list >> >> Xen-devel@lists.xensource.com >> >> http://lists.xensource.com/xen-devel >> >> >> > >> > Looks like it is called dom0_max_vcpus in 3.4.2: >> > >> > cat xen-3.4.2.gz |gzip -d | strings | grep cpus | grep dom0 >> > dom0_vcpus_pin >> > dom0_max_vcpus >> > >> > Andy >> > >> >> Also see this thread >> http://article.gmane.org/gmane.comp.emulators.xen.devel/69017, which >> seems to suggest that dom0_max_vcpus is parameter for the Xen >> hypervisor (xen.gz) itself, while dom0_vcpus is for the dom0 kernel >> and causes it to hot-unplug the "extra" cpu''s so that they can be >> (re)added later. >> >> I believe the xen 2.6.18 kernel also supports booting pv domUs with >> more max-cpus than active at startup, again so that they can be added >> later. >> >> I guess dom0_vcpus only works with Xen 2.6.18, I can find no trace of >> it in the openSUSE Xen kernel source. >> > > I''ve been using dom0_vcpus for Xen *hypervisor* with RHEL5/CentOS5 (which includes Xen 3.1.2.) > > I think you mixed that up with xend-config.sxp dom0-cpus option, which > is totally different thing, like Keir explains in that thread.If you google dom0-cpus there are examples of other users passing the argument to Xen or dom0, but yeh, good chance they are confused too :-) Andy> > But yeah, maybe now I remember it''s called dom0_max_vcpus nowadays. > Thanks. > > -- Pasi > >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Pasi Kärkkäinen
2010-Jan-13 22:04 UTC
Re: [Xen-devel] Xen hypervisor dom0_vcpus option broken in Xen 3.4 ?
On Wed, Jan 13, 2010 at 09:54:56PM +0000, Andrew Lyon wrote:> On Wed, Jan 13, 2010 at 9:52 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote: > > On Wed, Jan 13, 2010 at 09:47:38PM +0000, Andrew Lyon wrote: > >> On Wed, Jan 13, 2010 at 9:38 PM, Andrew Lyon <andrew.lyon@gmail.com> wrote: > >> > On Wed, Jan 13, 2010 at 8:36 PM, Pasi Kärkkäinen <pasik@iki.fi> wrote: > >> >> Hello, > >> >> > >> >> while discussing things on xen-users we noticed this: > >> >> > >> >> (XEN) Xen version 3.4.2 (root@(none)) (gcc version 4.4.2 20091027 (RedHat 4.4.2-7) (GCC) ) Mon Dec 14 06:53:18 EET 2009 > >> >> (XEN) Latest ChangeSet: unavailable > >> >> (XEN) Command line: dom0_mem=1G loglvl=all guest_loglvl=all com1=38400,8n1 console=com1 dom0_vcpus=1 > >> >> .. > >> >> (XEN) Dom0 has maximum 4 VCPUs > >> >> .. > >> >> > >> >> Has dom0_vcpus option name changed, or is it just broken? > >> >> > >> >> -- Pasi > >> >> > >> >> > >> >> _______________________________________________ > >> >> Xen-devel mailing list > >> >> Xen-devel@lists.xensource.com > >> >> http://lists.xensource.com/xen-devel > >> >> > >> > > >> > Looks like it is called dom0_max_vcpus in 3.4.2: > >> > > >> > cat xen-3.4.2.gz |gzip -d | strings | grep cpus | grep dom0 > >> > dom0_vcpus_pin > >> > dom0_max_vcpus > >> > > >> > Andy > >> > > >> > >> Also see this thread > >> http://article.gmane.org/gmane.comp.emulators.xen.devel/69017, which > >> seems to suggest that dom0_max_vcpus is parameter for the Xen > >> hypervisor (xen.gz) itself, while dom0_vcpus is for the dom0 kernel > >> and causes it to hot-unplug the "extra" cpu''s so that they can be > >> (re)added later. > >> > >> I believe the xen 2.6.18 kernel also supports booting pv domUs with > >> more max-cpus than active at startup, again so that they can be added > >> later. > >> > >> I guess dom0_vcpus only works with Xen 2.6.18, I can find no trace of > >> it in the openSUSE Xen kernel source. > >> > > > > I''ve been using dom0_vcpus for Xen *hypervisor* with RHEL5/CentOS5 (which includes Xen 3.1.2.) > > > > I think you mixed that up with xend-config.sxp dom0-cpus option, which > > is totally different thing, like Keir explains in that thread. > > If you google dom0-cpus there are examples of other users passing the > argument to Xen or dom0, but yeh, good chance they are confused too > :-) >Indeed :) I just verified with Xen 3.4.2, setting dom0_max_vcpus=1 for xen.gz in grub.conf works OK and limits the amount of vcpus for dom0 to 1. So now let''s put the other related settings here aswell, for google archives: Xen 3.4 hypervisor (xen.gz) boot time options for grub.conf: dom0_max_vcpus=X dom0_vcpus_pin dom0_mem=512M Xend configuration options in /etc/xen/xend-config.sxp: (dom0-cpus 1) (dom0-min-mem 512) (enable-dom0-ballooning no) Hopefully this helps future google searches :) -- Pasi _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel