One of the reasons for lack of progress in multiprocessor systems was the
inefficiency of parallelism of the programs—see Chap. 17 of this book and ERA
paper [1, 2].
Another reason was the inefficiency of synchronization of processes within the
system. Hopefully, this chapter will not cause extra skepticism from the past but
some observation of the known drawbacks in concurrency and attract researchers to
develop along proposed concept for possible improvement in the future resilient
systems.
12.2.2 Why It Is Needed
Concurrency of the computer system is required due to several hardware subsystems operation at the same time and at some points compete for resources and
sooner or later they compete for any of resources.
Resources are defined in [1, 2] and, namely, for computer systems they are
structure, information, and time.
Some examples of concurrency presence are
• multiprocessor system (processes within various parts of hardware);
• databases, especially distributed ones;
• I/O devices interactions;
• router servicing of packets system.
In terms of computer hierarchy, concurrency of computing might occur and be
supported at levels of
– machine instruction,
– high-level language statement,
– module, and
– program.
So far, there is no introduction at the language level of special operators for concurrency of processes, while in the structure of runtime system two main monitors
as above are dealing with a concurrency of processes.
At the instruction of hardware, there are known concurrency instructions that
were implemented since the late 50s of the past century. Two further figures—taken
from [3] describe concurrency levels of presentation and appearance in the system
and system main elements and layers (Figs. 12.2 and 12.3).
There is no doubt that amount of entries related to concurrency in the web and
intensity of research and development is high. The point is through—quite a few—
are dealing with algebra representations, and very few, if any, address the real
problems or requirements—PRE: Performance-, Reliability-, Energy–efficiency of
concurrency handling.
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12 Proposed Runtime System Structure …
inefficiency of parallelism of the programs—see Chap. 17 of this book and ERA
paper [1, 2].
Another reason was the inefficiency of synchronization of processes within the
system. Hopefully, this chapter will not cause extra skepticism from the past but
some observation of the known drawbacks in concurrency and attract researchers to
develop along proposed concept for possible improvement in the future resilient
systems.
12.2.2 Why It Is Needed
Concurrency of the computer system is required due to several hardware subsystems operation at the same time and at some points compete for resources and
sooner or later they compete for any of resources.
Resources are defined in [1, 2] and, namely, for computer systems they are
structure, information, and time.
Some examples of concurrency presence are
• multiprocessor system (processes within various parts of hardware);
• databases, especially distributed ones;
• I/O devices interactions;
• router servicing of packets system.
In terms of computer hierarchy, concurrency of computing might occur and be
supported at levels of
– machine instruction,
– high-level language statement,
– module, and
– program.
So far, there is no introduction at the language level of special operators for concurrency of processes, while in the structure of runtime system two main monitors
as above are dealing with a concurrency of processes.
At the instruction of hardware, there are known concurrency instructions that
were implemented since the late 50s of the past century. Two further figures—taken
from [3] describe concurrency levels of presentation and appearance in the system
and system main elements and layers (Figs. 12.2 and 12.3).
There is no doubt that amount of entries related to concurrency in the web and
intensity of research and development is high. The point is through—quite a few—
are dealing with algebra representations, and very few, if any, address the real
problems or requirements—PRE: Performance-, Reliability-, Energy–efficiency of
concurrency handling.
180
12 Proposed Runtime System Structure …