cpuset is a command used to restrict process to a defined processor and memory node
From the manual page:
A cpuset defines a list of CPUs and memory nodes.
The CPUs of a system include all the logical processing units on
which a process can execute, including, if present, multiple
processor cores within a package and Hyper-Threads within a processor
core. Memory nodes include all distinct banks of main memory; small
and SMP systems typically have just one memory node that contains all
the system's main memory, while NUMA (non-uniform memory access)
systems have multiple memory nodes.
Cpusets are represented as directories in a hierarchical pseudo-
filesystem, where the top directory in the hierarchy (/dev/cpuset)
represents the entire system (all online CPUs and memory nodes) and
any cpuset that is the child (descendant) of another parent cpuset
contains a subset of that parent's CPUs and memory nodes. The
directories and files representing cpusets have normal filesystem
permissions.
Every process in the system belongs to exactly one cpuset. A process
is confined to run only on the CPUs in the cpuset it belongs to, and
to allocate memory only on the memory nodes in that cpuset. When a
process fork(2)s, the child process is placed in the same cpuset as
its parent. With sufficient privilege, a process may be moved from
one cpuset to another and the allowed CPUs and memory nodes of an
existing cpuset may be changed.
When the system begins booting, a single cpuset is defined that
includes all CPUs and memory nodes on the system, and all processes
are in that cpuset. During the boot process, or later during normal
system operation, other cpusets may be created, as subdirectories of
this top cpuset, under the control of the system administrator, and
processes may be placed in these other cpusets.
Cpusets are integrated with the sched_setaffinity(2) scheduling
affinity mechanism and the mbind(2) and set_mempolicy(2) memory-
placement mechanisms in the kernel. Neither of these mechanisms let
a process make use of a CPU or memory node that is not allowed by
that process's cpuset. If changes to a process's cpuset placement
conflict with these other mechanisms, then cpuset placement is
enforced even if it means overriding these other mechanisms. The
kernel accomplishes this overriding by silently restricting the CPUs
and memory nodes requested by these other mechanisms to those allowed
by the invoking process's cpuset. This can result in these other
calls returning an error, if for example, such a call ends up
requesting an empty set of CPUs or memory nodes, after that request
is restricted to the invoking process's cpuset.
Typically, a cpuset is used to manage the CPU and memory-node
confinement for a set of cooperating processes such as a batch
scheduler job, and these other mechanisms are used to manage the
placement of individual processes or memory regions within that set
or job.
