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| author | Eduardo Habkost <ehabkost@redhat.com> | 2017-01-23 16:06:32 -0200 |
|---|---|---|
| committer | Eduardo Habkost <ehabkost@redhat.com> | 2017-03-03 10:08:03 -0300 |
| commit | 4b9a5dd762ae41acd7df741de3e554b319a2cced (patch) | |
| tree | 5b64eb675a4e36211cbed3f6da9aea6bbabb6200 /qemu-options.hx | |
| parent | 508e038a5d725f2aa729f58a1f5209b9be4227de (diff) | |
| download | qemu-4b9a5dd762ae41acd7df741de3e554b319a2cced.tar.gz | |
qemu-options: Rewrite -numa documentation
Rewrite the -numa documentation to clarify what exactly it does.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20170123180632.28942-3-ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Diffstat (limited to 'qemu-options.hx')
| -rw-r--r-- | qemu-options.hx | 38 |
1 files changed, 28 insertions, 10 deletions
diff --git a/qemu-options.hx b/qemu-options.hx index c85f77d1d8..229243831b 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -144,16 +144,34 @@ STEXI @item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] @itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] @findex -numa -Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev} -and @samp{cpus} are omitted, resources are split equally. Also, note -that the -@option{numa} option doesn't allocate any of the specified -resources. That is, it just assigns existing resources to NUMA nodes. This -means that one still has to use the @option{-m}, @option{-smp} options -to allocate RAM and VCPUs respectively, and possibly @option{-object} -to specify the memory backend for the @samp{memdev} suboption. - -@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one -node uses @samp{memdev}, all of them have to use it. +Define a NUMA node and assign RAM and VCPUs to it. + +@var{firstcpu} and @var{lastcpu} are CPU indexes. Each +@samp{cpus} option represent a contiguous range of CPU indexes +(or a single VCPU if @var{lastcpu} is omitted). A non-contiguous +set of VCPUs can be represented by providing multiple @samp{cpus} +options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically +split between them. + +For example, the following option assigns VCPUs 0, 1, 2 and 5 to +a NUMA node: +@example +-numa node,cpus=0-2,cpus=5 +@end example + +@samp{mem} assigns a given RAM amount to a node. @samp{memdev} +assigns RAM from a given memory backend device to a node. If +@samp{mem} and @samp{memdev} are omitted in all nodes, RAM is +split equally between them. + +@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, +if one node uses @samp{memdev}, all of them have to use it. + +Note that the -@option{numa} option doesn't allocate any of the +specified resources, it just assigns existing resources to NUMA +nodes. This means that one still has to use the @option{-m}, +@option{-smp} options to allocate RAM and VCPUs respectively. + ETEXI DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, |