問61
頻出度★★★
コンピュータシステムが単位時間当たりに処理できるジョブやトランザクションなどの処理件数のことであり，コンピュータの処理能力を表すものはどれか。
平成21年度 秋期 ITパスポート試験 問61
テクノロジ系システム構成要素 › システムの評価指標
This question's explanation and your answers so far.
解説
問 61
Incorrectア
Access time is the amount of *time* required from issuing a read or write instruction to a storage device until the data transfer is complete. It measures the speed of a single device, not the number of items processed per unit of time.
- イ
正解 Throughput is a performance measure that indicates the number of jobs or transactions a computer system can process per unit of time — exactly the definition given in the question. Its units are things like items per second, transactions per second (tps), or jobs per hour. Because it expresses the amount of processing done, it measures the overall processing capability of the system (how much work it can get through). Reducing idle CPU time with spooling or multiprogramming raises throughput.
Incorrectウ
A timestamp is date-and-time information showing *when* data or a process occurred. It is used to prove the existence of an electronic document or to manage the order of log records; it is not a performance measure.
Incorrectエ
Response time is the *time* from when a user finishes submitting a request until the response begins to come back. It measures how long the user waits for a single request, which is a different viewpoint from throughput, the number of items processed per unit of time.
ここがポイント
- Throughput = the number of items processed per unit of time (the volume of processing). It is the representative measure of a system's overall processing capability.
- Distinguish performance measures by whether they count *amount* or measure *time*: throughput counts items, while response time, turnaround time, and access time measure time.
用語