here - Stefan-Marr.de

3.3. Common Problems for the Implementation of Concurrency Abstractions
of them. As argued above in Sec. 3.2.4, this dissertation focuses on concepts
that require support for an enforcement of their semantics on the part of the
VM. Based on the distinction provided by the two definitions, this dissertation
focuses on the set of concurrent programming concepts, i. e., the concepts that
are meant to support algorithms to yield consistent and correct results.
3.2.4.3. Conclusions
This survey discussed a wide range of concepts for concurrent and parallel
programming. It categorizes the concepts identified in literature and programming
languages based on answering the question of whether their semantics
benefit from an enforcement in the VM and the question of whether their
performance could significantly benefit from VM support.
Parallel programming concepts benefit most from flexible infrastructure for
performance optimizations, while concurrent programming concepts require
support from the VM in order to enforce their semantics.
The remainder of this dissertation focuses on concurrent programming concepts,
i. e., concepts that require support from the VM to guarantee correct
semantics, and proposes a unifying substrate for concurrent programming.
3.3. Common Problems for the Implementation of
Concurrency Abstractions
The previous section concluded that a wide range of concurrent programming
concepts require runtime support to enforce their semantics in an efficient
way. This section discusses the semantic issues of these concepts in more
detail. The analysis is based on the work of Karmani et al. [2009] who identified
and discussed a number of problems in the context of actor-oriented
frameworks, as well as examples from our own experiences in implementing
concurrent languages [Marr et al., 2010a, 2011a,b, 2012] that are problematic
for multi-language VMs. The in-depth investigation of these problems prepares,
as the main result of this chapter, the formulation of requirements for
multi-language VMs.
3.3.1. Overview
Karmani et al. surveyed actor-oriented frameworks for the JVM to assess
which semantics these frameworks provide and what the performance cost
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