38 lines
1.3 KiB
Racket
38 lines
1.3 KiB
Racket
#reader(lib "docreader.ss" "scribble")
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@require[(lib "bnf.ss" "scribble")]
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@require["mz.ss"]
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@title[#:tag "mz:threadgroups"]{Thread Groups}
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A @deftech{thread group} is a collection of threads and other thread
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groups that have equal claim to the CPU. By nesting thread groups and
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by creating certain threads within certain groups, a programmer can
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control the amount of CPU allocated to a set of threads. Every thread
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belongs to a thread group, which is determined by the
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@scheme[current-thread-group] parameter when the thread is
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created. Thread groups and custodians (see @secref["mz:custodians"])
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are independent.
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The root thread group receives all of the CPU that the operating
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system gives Scheme. Every thread or nested group in a particular
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thread group receives equal allocation of the CPU (a portion of the
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group's access), although a thread may relinquish part of its
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allocation by sleeping or synchronizing with other processes.
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@defproc[(make-thread-group [group thread-group? (current-thread-group)])
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thread-group?]{
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Creates a new thread group that belongs to @scheme[group].}
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@defproc[(thread-group? [v any/c]) boolean?]{
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Returns @scheme[#t] if @scheme[v] is a thread group value, @scheme[#f]
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otherwise.}
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@defparam[current-thread-group group thread-group?]{
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A parameter that determines the thread group for newly created
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threads.}
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