So far, the <cell/> element can have two types of children
elements: <distances/> and <cache/> (which can be repeated more
times). However, there is no reason to require specific order in
input XML. Allow elements to be interleaved.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
To cite ACPI specification:
Heterogeneous Memory Attribute Table describes the memory
attributes, such as memory side cache attributes and bandwidth
and latency details, related to the System Physical Address
(SPA) Memory Ranges. The software is expected to use this
information as hint for optimization.
According to our upstream discussion [1] this is exposed under
<numa/> as <cache/> under NUMA <cell/> and <latency> or
<bandwidth/> under numa/latencies.
1: https://www.redhat.com/archives/libvir-list/2020-January/msg00422.html
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
QEMU allows creating NUMA nodes that have memory only.
These are somehow important for HMAT.
With check done in qemuValidateDomainDef() for QEMU 2.7 or newer
(checked via QEMU_CAPS_NUMA), we can be sure that the vCPUs are
fully assigned to NUMA nodes in domain XML.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Recently CPU hardware vendors have started to support a new structure
inside the CPU package topology known as a "die". Thus the hierarchy
is now:
sockets > dies > cores > threads
This adds support for "dies" in the XML parser, with the value
defaulting to 1 if not specified for backwards compatibility.
For example a system with 64 logical CPUs might report
<topology sockets="4" dies="2" cores="4" threads="2"/>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
QEMU has possibility to call madvise(.., MADV_REMOVE) in some
cases. Expose this feature to users by new element/attribute
discard.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Add support for describing NUMA distances in a domain's <numa> <cell>
XML description.
Below is an example of a 4 node setup:
<cpu>
<numa>
<cell id='0' cpus='0-3' memory='2097152' unit='KiB'>
<distances>
<sibling id='0' value='10'/>
<sibling id='1' value='21'/>
<sibling id='2' value='31'/>
<sibling id='3' value='21'/>
</distances>
</cell>
<cell id='1' cpus='4-7' memory='2097152' unit='KiB'>
<distances>
<sibling id='0' value='21'/>
<sibling id='1' value='10'/>
<sibling id='2' value='21'/>
<sibling id='3' value='31'/>
</distances>
</cell>
<cell id='2' cpus='8-11' memory='2097152' unit='KiB'>
<distances>
<sibling id='0' value='31'/>
<sibling id='1' value='21'/>
<sibling id='2' value='10'/>
<sibling id='3' value='21'/>
</distances>
<cell id='3' cpus='12-15' memory='2097152' unit='KiB'>
<distances>
<sibling id='0' value='21'/>
<sibling id='1' value='31'/>
<sibling id='2' value='21'/>
<sibling id='3' value='10'/>
</distances>
</cell>
</numa>
</cpu>
A <cell> defines a NUMA node. <distances> describes the NUMA distance
from the <cell> to the other NUMA nodes (the <sibling>s). For example,
in above XML description, the distance between NUMA node0 <cell id='0'
...> and NUMA node2 <sibling id='2' ...> is 31.
Valid distance values are '10 <= value <= 255'. A distance value of 10
represents the distance to the node itself. A distance value of 20
represents the default value for remote nodes but other values are
possible depending on the physical topology of the system.
When distances are not fully described, any missing sibling distance
values will default to 10 for local nodes and 20 for remote nodes.
If distance is given for A -> B, then we default B -> A to the same
value instead of 20.
Signed-off-by: Wim ten Have <wim.ten.have@oracle.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
This patch introduces
<cache level='N' mode='emulate'/>
<cache mode='passthrough'/>
<cache mode='disable'/>
sub element of /domain/cpu. Currently only a single <cache> element is
allowed.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The attribute can be used to request a specific way of checking whether
the virtual CPU matches created by the hypervisor matches the
specification in domain XML.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
