IPA IP 2020 Question 61
A question IPA Japan published in 令和2年度 10月 ITパスポート試験 公開問題 問61, translated into English. ITPEC is based on the same exams.
Which of the following is the appropriate combination of terms to be inserted into blanks A and B in the following description concerning measures for improving server performance?
In a certain system, the increase in the processing time of the server has become a problem as the number of processed transactions increases. As a measure for improving the processing performance of the server, handling this by increasing the number of servers and having them perform parallel processing is called A. Handling this by replacing the server itself with a high-performance one, or by replacing the CPU, main memory, and other such components with ones of better performance is called B.
Explanation
A: scale-out, B: scale-up — more servers working in parallel scale a system out; a more powerful server scales it up.
- •Scale-out (horizontal scaling): add servers and spread the processing over them, usually behind a load balancer. It suits work that divides into many independent requests, such as web front ends.
- •Scale-up (vertical scaling): replace the server with a faster one, or fit a faster CPU, more main memory and other better components. The software needs no change, but one machine has an upper limit.
The description's first measure increases the number of servers and processes in parallel, so it is scale-out; the second improves the server itself, so it is scale-up.
Answer (a)
Why not others:
- •(b) — swaps the two terms: adding servers is scale-out, not scale-up
- •(c) — the A measure adds servers, which is not scale-up, and downsizing is not improving a server's components
- •(d) — downsizing means moving work from a mainframe to smaller servers or PCs to cut cost, not adding servers for performance
Key rule: Scale out = more machines in parallel; scale up = a stronger single machine.
System Component · AI-written, may contain errors
This question comes from the past questions IPA Japan publishes, translated into English by ITPEC Practice. ITPEC Practice is an independent study tool and is not affiliated with IPA or ITPEC. See the original paper (PDF) or Report an issue.