>>>> This kernel works as expected with one exception. The exception has been >>>> a nagging problem, but I have not reported it because 1) we are using >>>> a research OS in DomU and 2) we are not clear if the problem is in our >>>> code, Linux or Xen. But, here are the symptoms: >>>> >>>> Occasionally (this seems to correlate to network activity between Dom0 >>>> and DomU), the system becomes unresponsive. I am running the Michael >>>> Young kernel at runlevel 3 within Dom0 (very little memory used by >>>> applications). Our OS runs in DomU and is constrained to 128MB of >>>> memory. When the system is unresponsive, typing a character into a >>>> Dom0 console take 2-5 seconds to appear on the screen. Likewise, other >>>> activity is extremely slow. As I mentioned, we have not been able to >>>> isolate where the problem is. Running, for example, an OpenWrt Linux >>>> build in DomU does not have this problem. >>> I have seen something similar, though I don't know where the fault >>> lies either. >> That is somewhat good to hear. I have today solved this problem by running >> "xm vcpu-set Domain-0 1." By default, Xen assigned Dom0 all of my cores >> (two). Reducing this to one solves the problem for me. I am working on >> a better write up that I'll send to fedora-xen and possibly the upstream >> Xen mailing list. I have not decided if this is a bug and am having some >> discussions locally that may help me formulate a better inquiry. > Usually it's better to use dom0_max_vcpus=1 on the grub xen.gz line.
So, is this a known "issue." Is it typically best practice to limit Dom0 to one core? I've seen systems where this is not a problem (dom0_max_vcpus=n works fine, where n is the number of cores) and others where it is. Why would this be? -- Mike :wq -- xen mailing list xen@lists.fedoraproject.org https://admin.fedoraproject.org/mailman/listinfo/xen
