doc: Update CPU pinning documentation for containers

Signed-off-by: Kadin Sayani <[email protected]>

doc/reference/instance_options.md

@@ -99,8 +99,7 @@ You have different options to limit CPU usage:
   This option is available only for containers.
   See {ref}`instance-options-limits-cpu-container` for how to set this option.
 - Set {config:option}`instance-resource-limits:limits.cpu.pin_strategy` to specify the strategy for virtual-machine CPU auto pinning.
-  This option is available only for virtual machines.
-  See {ref}`instance-options-limits-cpu-vm` for how to set this option.
+  See {ref}`instance-options-limits-cpu` for how to set this option.
 
 It is possible to set both options at the same time to restrict both which CPUs are visible to the instance and the allowed usage of those instances.
 However, if you use {config:option}`instance-resource-limits:limits.cpu.allowance` with a time limit, you should avoid using {config:option}`instance-resource-limits:limits.cpu` in addition, because that puts a lot of constraints on the scheduler and might lead to less efficient allocations.
@@ -117,7 +116,7 @@ You can specify either which CPUs or how many CPUs are visible and available to
 
   To pin to a single CPU, use the range syntax (for example, `1-1`) to differentiate it from a number of CPUs.
 - If you specify a number (for example, `4`) of CPUs, LXD will do dynamic load-balancing of all instances that aren't pinned to specific CPUs, trying to spread the load on the machine.
-  Instances are re-balanced every time an instance starts or stops, as well as whenever a CPU is added to the system.
+  When `instance-resource-limits:limits.cpu.pin_strategy` is set to `auto`, instances are re-balanced every time an instance starts or stops, as well as whenever a CPU is added to the system.
 
 (instance-options-limits-cpu-vm)=
 ##### CPU limits for virtual machines