Why is the ordering of instructions in a Dockerfile important for build performance?
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Incorrect.
The correct answer is B) Docker caches layers and invalidates the cache for a layer and all subsequent layers once a change is detected, so placing rarely-changing steps (dependency installs) before frequently-changing ones (copying source code) maximizes cache reuse
Correct Answer
Docker caches layers and invalidates the cache for a layer and all subsequent layers once a change is detected, so placing rarely-changing steps (dependency installs) before frequently-changing ones (copying source code) maximizes cache reuse
Since a cache miss on one layer invalidates all subsequent layers, placing stable steps (installing dependencies) early and frequently-changing steps (copying app code) later avoids unnecessary re-execution of expensive steps.