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2. Context and Motivation
First, it discussed the notion of multi-language VMs as general purpose
platforms, which are used for a wide range of applications. Language implementers
need to be supported in implementing abstractions for concurrent
and parallel programming to enable VMs to remain general purpose
platforms. Furthermore, VMs need unifying abstractions for that support, because
supporting a wide range of independent features in a VM is infeasible.
Second, this chapter briefly revisited the background behind the multicore
revolution, which increases the need to support concurrent and parallel programming
in VMs. Multicore processors will play a major role for the foreseeable
future and therefore, software developers will need to utilize them to
satisfy their application’s performance requirements.
Third, this chapter proposed the notions of concurrent programming and parallel
programming to enable the categorization of the corresponding programming
concepts based on their intent, realizing two distinct sets of concepts.
Concurrent programming concepts are meant to coordinate modification of
shared resources, while parallel programming concepts are meant to coordinate
parallel activities to compute a common result.
Fourth, a partial taxonomy is proposed to categorize concurrent and parallel
programming concepts into threads and locks, communicating threads, communicating
isolates, and data parallelism. This chapter discusses a number of
concepts based on this categorization and details Clojure agents, because they
are used in the remainder of this dissertation as a running example.
Finally, the chapter concludes with a vision on how to build applications in
the multicore era. Applications need to be able to exploit concurrency and parallelism,
and software developers want to utilize appropriate programming
abstractions for the different parts of an application to achieve their goals.
With this vision in mind, the next chapter discusses the question of which
concurrent and parallel programming concepts multi-language VMs needs to
support.
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