6.5.1

Table 5‑2. Supported Features for Virtual Machine Compatibility (Continued)
Feature
ESXi 6.5 and
later
ESXi 6.0 and
later
ESXi 5.5 and
later
ESXi 5.1 and
later
ESXi 5.0 and
later
ESX/ESXi
4.x and
later
ESX/ESXi
3.5 and later
Parallel
ports
3 3 3 3 3 3 3
Floppy
devices
2 2 2 2 2 2 2
Virtual CPU Configuration
You can add, change, or configure CPU resources to improve virtual machine performance. You can set
most of the CPU parameters when you create virtual machines or after the guest operating system is
installed. Some actions require that you power off the virtual machine before you change the settings.
VMware uses the following terminology. Understanding these terms can help you plan your strategy for
CPU resource allocation.
CPU The CPU, or processor, is the component of a computer system that
performs the tasks required for computer applications to run. The CPU is
the primary element that performs the computer functions. CPUs contain
cores.
CPU Socket A CPU socket is a physical connector on a computer motherboard that
connects to a single physical CPU. Some motherboards have multiple
sockets and can connect multiple multicore processors (CPUs).
Core A core contains a unit containing an L1 cache and functional units needed
to run applications. Cores can independently run applications or threads.
One or more cores can exist on a single CPU.
Corelet An AMD processor corelet is architecturally equivalent to a logical
processor. Certain future AMD processors contain multiple compute units,
each of which has several corelets. Unlike a traditional processor core, a
corelet lacks a complete set of private, dedicated execution resources. So,
the corelet shares some execution resources, such as an L1 instruction
cache or a floating-point execution unit, with other corelets. AMD refers to
corelets as cores. However, these corelets are unlike traditional cores and
they are called corelets in VMware documentation to make resource
sharing more apparent.
Thread Some cores can run independent streams of instructions simultaneously. In
existing implementations, cores can run one or two software threads at one
time by multiplexing the functional units of the core between the software
threads, as necessary. Such cores are called dual or multithreaded.
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