DynamoDB spreads your table across partitions, but your traffic rarely spreads evenly. Burst capacity and adaptive capacity are the two automatic mechanisms that stop a skewed workload from throttling — until it hits a hard limit.
What is DynamoDB adaptive capacity?
DynamoDB adaptive capacity is an automatic mechanism that shifts unused throughput toward a hot partition so a skewed key doesn't throttle while the rest of the table sits idle. Paired with burst capacity, it absorbs spikes and sustained skew for free — but it can't push a single key past the partition ceiling.
Burst capacity lends you up to 5 minutes (300 seconds) of unused throughput to ride out short spikes. It's a buffer, not a feature you tune.
Adaptive capacity automatically raises throughput for a "hot" partition — drawing from the rest of your table's unused capacity — so a skewed key doesn't throttle.
