From e626a8c7f06c85584f4285c51bea1a7ed76a25f7 Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Tue, 11 Sep 2012 12:26:25 +0200 Subject: x86: make the dom0_max_vcpus option more flexible The dom0_max_vcpus command line option only allows the exact number of VCPUs for dom0 to be set. It is not possible to say "up to N VCPUs but no more than the number physically present." Allow a range for the option to set a minimum number of VCPUs, and a maximum which does not exceed the number of PCPUs. For example, with "dom0_max_vcpus=4-8": PCPUs Dom0 VCPUs 2 4 4 4 6 6 8 8 10 8 Existing command lines with "dom0_max_vcpus=N" still work as before (and are equivalent to dom0_max_vcpus=N-N). Signed-off-by: David Vrabel Committed-by: Jan Beulich --- docs/misc/xen-command-line.markdown | 29 ++++++++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-) (limited to 'docs/misc') diff --git a/docs/misc/xen-command-line.markdown b/docs/misc/xen-command-line.markdown index eff930f7f8..92fa8fcd26 100644 --- a/docs/misc/xen-command-line.markdown +++ b/docs/misc/xen-command-line.markdown @@ -378,10 +378,33 @@ Specify the bit width of the DMA heap. Specify a list of IO ports to be excluded from dom0 access. ### dom0\_max\_vcpus -> `= ` -Specify the maximum number of vcpus to give to dom0. This defaults -to the number of pcpus on the host. +Either: + +> `= `. + +The number of VCPUs to give to dom0. This number of VCPUs can be more +than the number of PCPUs on the host. The default is the number of +PCPUs. + +Or: + +> `= -` where `` and `` are integers. + +Gives dom0 a number of VCPUs equal to the number of PCPUs, but always +at least `` and no more than ``. Using `` may give +more VCPUs than PCPUs. `` or `` may be omitted and the +defaults of 1 and unlimited respectively are used instead. + +For example, with `dom0_max_vcpus=4-8`: + + Number of + PCPUs | Dom0 VCPUs + 2 | 4 + 4 | 4 + 6 | 6 + 8 | 8 + 10 | 8 ### dom0\_mem > `= List of ( min: | max: | )` -- cgit v1.2.3