Developer Guide

  • 2021.2
  • 06/11/2021
  • Public
Contents

Terminology

best known configuration (BKC)
A set of components needed to construct a proven stable platform.
cache way
Smallest portion of cache that can be reserved via Intel® TCC Tools. The size of one cache way varies depending on processor and cache level.
capsule
Binary used to change a system’s tuning configuration by updating certain areas of the firmware, known as “subregions.”
cycle time
The amount of time allotted to complete the cyclic workload.
deadline
The time when some computation or data must complete or arrive. For some applications, computations or data that arrive late are no longer useful.
fabric
The interconnect technology the carries on-chip communications between the different functional components of the processor.
Intel® Time Coordinated Computing (Intel® TCC)
A modern approach to architecting distributed, synchronized, scalable computing systems that address real-time application requirements for cyber-physical systems (CPS). Intel® TCC moves beyond traditional real-time systems based on simple microcontrollers.
isochronous cyclic workload
A code sequence that runs repeatedly (“cyclic workload”) and has a deadline that each cycle must meet (“isochronous”). Stand-alone real-time applications fit into this category.
jitter
The difference between maximum and minimum of some quantity, such as latency measured in units of time. Jitter matters a lot at sensors and actuators, but other mechanisms (such as TSN mechanisms) typically hide software-execution jitter (so long as WCET bounds are satisfied).
latency
The duration of time between two events; for example, the time a signal is detected, and a response is received, or the time between an application sending a UDP message until it arrives on the Ethernet wire, or the time required to execute a code segment.
noisy neighbor
An application or device, the functioning of which, affects the device or application with temporal requirements (e.g., because of shared resources). Temporal isolation seeks to reduce the deleterious effect of a noisy neighbor.
real-time application
An application that has a requirement to complete execution within some WCET with a specified level of reliability. For example, “Has to finish running every millisecond without missing a deadline in 7 days.” Typically, a real-time application contains a sequence of three tasks: sense > compute > actuate and increasingly uses a network to interconnect these. The extent to which a missed deadline impacts the overall system is sometimes described using “soft”, “firm”, and “hard” real time, but we avoid these terms, preferring to quantify the reliability with number of 9s.
temporal isolation
A property of real-time systems that minimizes the impact of best-effort workloads on WCET of a real-time workload running on the system.
time synchronization
The degree to which two or more systems or devices agree on what time it is, to within some maximum error. Enables sensors, compute systems, actuators, and network elements to operate on a global schedule. Enables time-coordinated computing devices to time-division multiplex real-time and non-real-time tasks, measure latencies, and detect violation of deadlines. Enables an RTOS to schedule a task at a specific time.
workload
An application that performs some useful computational work, including (perhaps) receiving input, performing computation, and generating an output.
worst-case execution time (WCET)
The maximum measured latency of the compute portion of an application, across multiple iterations. WCET relates to reliability, described by “the number of 9s”. For instance, a reliability of two 9s refers to missing the deadline 1 out of 100 times.

Product and Performance Information

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Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.