unt</code>.</p></li></ol><h2 id=understanding-rate-limits>Understanding rate limits</h2><p>In the preceding examples you saw how Mixer applies rate limits to requests
that match certain conditions.</p><p>Every named quota instance like <code>requestcount</code> represents a set of counters.
The set is defined by a Cartesian product of all quota dimensions. If the
number of requests in the last <code>expiration</code> duration exceed <code>maxAmount</code>,
Mixer returns a <code>RESOURCE_EXHAUSTED</code> mes