# Synchronized parallel computation and slowdown of translators

## Abstract

The underlying parallel computers are assumed to be MIMD machines [Ku] with m≥1 synchronized and independent homogeneous processors [Ba], and parallel program schemes for them are introduced and studied. In section 1 usual (serial) program schemes and their function equivalence are introduced. In section 2 parallel program schemes are introduced as extensions of [Ma] and the main theorem is proved that each parallel program scheme can be translated into an m-parallel one where m≥1 is prescribed. In section 3 variable-free permit schemes without tests [Cu5] are introduced, and in section 4 their addressings are admitted. The functionality of permit schemes is investigated expecially for non-terminating processes (controlled by "semaphors" [Di], [LS]). In section 5 the parallel defect and the slowdown of a translator are introduced in all generality for arbitrary time unbounded program schemes.

## Keywords

Parallel Program Computation Rule Parallel Defect Permit Scheme Rooted Graph## Preview

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