Hi Running Xen 4.1.x Reading about schedulers, I normally give 1-2 cores to dom-0, reading about schedulers it say that we can give a dedicate core to the dom-0 or increase scheduler +256. What is the rule? can both? Thanks!!!
On Tue, 2012-07-24 at 22:06 -0700, Periko Support wrote:> Hi Running Xen 4.1.x >Hi,> Reading about schedulers, I normally give 1-2 cores to dom-0, reading > about schedulers it say that we can give a dedicate core to the dom-0 > or increase scheduler +256. > > What is the rule? can both? >Mmm... I''m not sure I''ve understood your question. However, the point is, depending on your configuration, it is possible that Dom0 will be performing some operation on behalf of the various DomUs. Besides than that, being able to access Dom0 for system maintenance purposes (such as killing/rebooting DomUs, etc) is something one wants to be always possible. For these reasons, it is often advised to act in such a way that Dom0 gets some chances to run, independently from what the DomUs do and from how much load that generates. Hence those rules you''re citing, which aim at achieving right this, although at different levels ad with different methods. No one of them is better than the other per-se, it really depends on your setup and on your workload. Finally, if you want to know if it''s possible to do both things, i.e., reserving one or more core for Dom0 AND boosting its scheduling priority, well, it is, but it''s also a bit pointless. :-P Regards, Dario -- <<This happens because I choose it to happen!>> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://retis.sssup.it/people/faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) _______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
On Wed, Jul 25, 2012 at 3:21 PM, Dario Faggioli <raistlin@linux.it> wrote:> On Tue, 2012-07-24 at 22:06 -0700, Periko Support wrote: >> Hi Running Xen 4.1.x >> > Hi, > >> Reading about schedulers, I normally give 1-2 cores to dom-0, reading >> about schedulers it say that we can give a dedicate core to the dom-0 >> or increase scheduler +256. >> >> What is the rule? can both? >> > Mmm... I''m not sure I''ve understood your question. However, the point > is, depending on your configuration, it is possible that Dom0 will be > performing some operation on behalf of the various DomUs. Besides than > that, being able to access Dom0 for system maintenance purposes (such as > killing/rebooting DomUs, etc) is something one wants to be always > possible. > > For these reasons, it is often advised to act in such a way that Dom0 > gets some chances to run, independently from what the DomUs do and from > how much load that generates. Hence those rules you''re citing, which aim > at achieving right this, although at different levels ad with different > methods. > > No one of them is better than the other per-se, it really depends on > your setup and on your workload. Finally, if you want to know if it''s > possible to do both things, i.e., reserving one or more core for Dom0 > AND boosting its scheduling priority, well, it is, but it''s also a bit > pointless. :-P > > Regards, > Dario > > -- > <<This happens because I choose it to happen!>> (Raistlin Majere) > ----------------------------------------------------------------- > Dario Faggioli, Ph.D, http://retis.sssup.it/people/faggioli > Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) > >I''m working on my lab, I will run some benchmark and see what happen, I''m on a learning curve, appreciate your info, thanks!!!