On Wed, Feb 20, 2008 at 5:08 PM, Frederic SOULIER <frederic.soulier at univ-tlse1.fr> wrote: > > I'm having issue with my Centos 5.1 /Xen installation. > I'm having some dom0 running 2.6.18-53.1.6.el5xen (x86_64). > On the dom0 where the load is high (more than 70% of total system memory > consumed by dom0 and domU) we have a lot of "memory squeeze ". > The result is that the domU seems to be blocked (no network/no disk > acces/ etc....). > > Looking for a solution in xen user list, it seems the problem come from > dom0 xen ballooning. > With this option the dom0 attempt to use the maximum of the system > memory and "balloon" is memory when new domU needs memory. > To resolve it, we have to fix the dom0 memory usage to avoid dom0 > ballooning and crash in our production environnemnt. > The solution seems to pass a parameter at xen boot time (in grub) to > limit dom0 memory usage : " dom0_mem=256M " > > As anyone encounter this type of problems ? > Is there any other solution than limitting dom0 memory usage ? I did not see the problems you are having but I have a set of Xen hosts and by default I limit the memory usage of the dom0 to 512MB using the dom0_mem option that you mentioned. In my case the dom0's are not doing anything so why do they need the memory in the first place ? That is why I've limited my dom0's like this by default, I consider this a good practice for these kinds of setups Regards, Tim -- Tim Verhoeven - tim.verhoeven.be at gmail.com - 0479 / 88 11 83 Hoping the problem magically goes away by ignoring it is the "microsoft approach to programming" and should never be allowed. (Linus Torvalds)