問60
頻出度★☆☆
PCの製品カタログに表のような項目の記載がある。これらの項目に関する記述のうち，適切なものはどれか。
| CPU |
|---|
| 動作周波数 |
| コア数／スレッド数 |
| キャッシュメモリ |
平成28年度 秋期 ITパスポート試験 問60
テクノロジ系コンピュータ構成要素 › プロセッサ
This question's explanation and your answers so far.
解説
問 60
Incorrectア
It is correct up to the point that the clock frequency indicates “the number of signals (clocks) generated per second that synchronize the timing of computation.” However, the CPU’s internal processing speed is “proportional” to the clock frequency, not “inversely proportional.” The higher the frequency, the more clocks there are per second and the faster the processing, so describing it as inversely proportional is wrong.
- イ
正解 A core (number of cores) refers to the central unit built into the CPU that performs computation. A CPU carrying 2 cores is called a dual-core CPU, and one carrying 4 cores is called a quad-core CPU; a CPU that has multiple cores like this is called a multi-core processor. As a rule, the more cores there are, the more processing can be executed in parallel, so improved performance can be expected. Option イ correctly states this definition and its concrete examples, so it is appropriate.
Incorrectウ
It is correct that the number of threads indicates “how many thread operations can be executed simultaneously,” but “the smaller the value, the faster” is wrong. The more threads that can run simultaneously (the larger the value), the more parallel processing proceeds, and generally the faster the processing becomes. The size relationship is reversed.
Incorrectエ
It is correct that cache memory is “a high-speed readable/writable storage device provided inside the CPU,” but the proximity to the core is reversed. The side closer to the CPU core is the primary (L1) cache, and the secondary (L2) cache is outside it; thus “the secondary cache is closer to the core than the primary cache” is wrong. In reality the primary cache is closer to the core, faster, and smaller in capacity.
ここがポイント
- The meanings of a CPU’s main specifications: clock frequency (clock = proportional to processing speed); number of cores / number of threads (the more, the better for parallel processing); cache memory (from nearest to the core: L1 → L2 → L3, the closer it is the faster and smaller in capacity).
- A core = the central computation unit inside the CPU. A CPU with multiple cores is a multi-core processor (dual-core = 2, quad-core = 4).
用語