FixWhat it doesTrade-off
Replicate the keySpreads the reads across the nodesCopies can disagree for a moment
Keep it in app memoryAnswers most reads in the app, so they never reach the nodeThe value can be a second or two old
Cap the reads for the keyLimits how many reads per second reach the nodeReads over the limit are held back, and what they get is a design choice
80%
Illustration, not a measurement. Arbitrary units.