Installation guide

C H A P T E R 1 2 VMware ESX Server Resource Management
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operating with the shared system resources provided by Hyper-Threading, and
can reduce performance.
• internal — Each CPU of the virtual machine can share logical CPUs with the
second CPU in the same virtual machine, but not with CPUs from other virtual
machines. This mode switches to none for virtual machines with one CPU.
Note: Only SMP virtual machines can use multiple virtual CPUs.
Using procfs
You can also use procfs to manage CPU resources. Use the following command:
echo <new_value> > <proc_filename>
in the service console, where <new_value> is the value you wish to set and
<proc_filename> is the full path name of the configuration option’s proc entry.
See Examples on page 399 for additional information.
Note: For SMP virtual machines, you can use the <id> of any of the virtual CPUs to
view or change configuration options for that virtual machine.
/proc/vmware/vm/<id>/cpu/min
Reading from this file reports the minimum CPU percentage allocated to the virtual
machine identified by <id>.
Specifying a percentage <minPercent>, to this file changes the minimum
percentage allocated to the virtual machine identified by <id> to <minPercent>.
The valid range of values for <minPercent> is 0 to 100 multiplied by the number
of virtual CPUs; that is, 100 percent for uniprocessor virtual machines, and 200 percent
for dual-virtual CPU virtual machines.
Note: If there is not enough unreserved CPU time available in the system to satisfy a
demand for an increase in min, then the reservation will not be changed.
/proc/vmware/vm/<id>/cpu/max
Reading from this file reports the maximum CPU percentage allocated to the virtual
machine identified by <id>.
Specifying a percentage <maxPercent>, to this file changes the maximum
percentage allocated to the virtual machine identified by <id> to <maxPercent>.
The valid range of values for <maxPercent> is 0 to 100 multiplied by the number
of virtual CPUs, or 100 percent for uniprocessor virtual machines, and 200 percent for
dual-virtual CPU virtual machines.
/proc/vmware/vm/<id>/cpu/shares
Reading from this file reports the number of shares allocated to the virtual machine
identified by <id>.