Why do you have to disable transformers if you want to measure reader performance?

Why do you have to disable transformers if you want to measure reader performance?

• A. Transformers always run slower than readers.
• B. Transformers always process data instantly.
• C. The log only reports the total workspace run time.
• D. FME begins processing features through transformers as soon as reading begins.

Answer: (D)

In FME, features start flowing through transformers as soon as they are read, so the time you see in the log includes both reading and any immediate transformation work. To measure just how fast the reader operates, you disable transformers so no downstream processing occurs during the read. That way the elapsed time reflects the reader’s performance alone, without additional overhead from transformation. The other statements don’t explain the measurement behavior: transformers aren’t guaranteed to always be slower or faster than readers, and while the log shows total workspace time, the real reason to disable transformers is to prevent immediate processing from skewing the read timing.

In FME, features start flowing through transformers as soon as they are read, so the time you see in the log includes both reading and any immediate transformation work. To measure just how fast the reader operates, you disable transformers so no downstream processing occurs during the read. That way the elapsed time reflects the reader’s performance alone, without additional overhead from transformation. The other statements don’t explain the measurement behavior: transformers aren’t guaranteed to always be slower or faster than readers, and while the log shows total workspace time, the real reason to disable transformers is to prevent immediate processing from skewing the read timing.