Linux / DevOps · Flashcard
What does the x-axis of a flame graph represent?
- AThe population of sampled stacks, sorted alphabetically to merge identical frames
- BThe passage of time, so a frame's horizontal position shows when it was executing
- CThe call order within each stack, from the first function called to the most recent
- DThe cumulative cost, so frames are placed left to right from cheapest to most expensive
Why this is the answer
A flame graph sorts frames alphabetically precisely so identical stacks merge into wide blocks; left-to-right position carries no meaning at all. Reading it as time is the most common mistake, and it describes a flame chart — a real and useful visualisation from browser profilers, which is why the confusion persists. Call order runs vertically, bottom to top, not horizontally. Sorting by cost is the largest-frame-left variant some tools offer, but it is not the default and is not what the axis means.
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