如果存在永久性的高速缓存丢失，CPU核心的工作负载（使用率）将是100％？ [英] Which one will workload(usage) of the CPU-Core if there is a persistent cache-miss, will be 100%?

问题描述

也就是说，如果核心处理器大部分时间都在等待来自具有RAM丢失的RAM或高速缓存L3的数据，但是系统是实时的（实时线程优先级），并且该线程是附加的（亲和性）并在不切换线程/上下文的情况下工作，那么在现代 x86_64 上应该显示什么样的负载（使用率）CPU-Core？

That is, if the core processor most of the time waiting for data from RAM or cache-L3 with cache-miss, but the system is a real-time (real-time thread priority), and the thread is attached (affinity) to the core and works without switching thread/context, what kind of load(usage) CPU-Core should show on modern x86_64?

也就是说，仅当登录 Idle 时，CPU使用率才会显示为减少？

That is, CPU usage is displayed as decrease only when logged in Idle?

如果有人知道，其行为是否与此不同，其他处理器的情况：ARM，Power [PC]，Sparc？

And if anyone knows, if the behavior is different in this case for other processors: ARM, Power[PC], Sparc?

说明：在OS-Windows的标准任务管理器中显示CPU使用情况

Clarification: shows CPU-usage in standard Task manager in OS-Windows

推荐答案

停留在高速缓存未命中的硬件线程（逻辑核心）无法做其他任何事情，因此仍然很重要忙于任务管理器/ CPU时间核算/ OS进程调度程序的时间片/诸如此类。

A hardware thread (logical core) that's stalled on a cache miss can't be doing anything else, so it still counts as busy for the purposes of task-managers / CPU time accounting / OS process scheduler time-slices / stuff like that.

在所有体系结构中都是如此。

This is true across all architectures.

没有超线程，硬件线程 /逻辑核心与物理核心相同。

Without hyperthreading, "hardware thread" / "logical core" are the same as a "physical core".

Morphcore /其他在超线程和功能更强大的单核之间进行即时更改可能会使保持许多执行单元繁忙的线程与被缓存阻塞的线程浪费很多时间之间存在差异

Morphcore / other on-the-fly changing between hyperthreading and a more powerful single core could make there be a difference between a thread that keeps many execution units busy, vs. a thread that is blocked on cache misses a lot of the time.

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