13.8 Thread Groups
A thread group is a collection of threads and other thread
groups that have equal claim to the CPU. By nesting thread groups and
by creating certain threads within certain groups, a programmer can
control the amount of CPU allocated to a set of threads. Every thread
belongs to a thread group, which is determined by the
current-thread-group parameter when the thread is
created. Thread groups and custodians (see Custodians)
are independent.
The root thread group receives all of the CPU that the operating
system gives Racket. Every thread or nested group in a particular
thread group receives equal allocation of the CPU (a portion of the
group’s access), although a thread may relinquish part of its
allocation by sleeping or synchronizing with other processes.
Creates a new thread group that belongs to group.
Returns #t if v is a thread group value, #f
otherwise.
A parameter that determines the thread group for newly created
threads.