ed for every request handled by an Istio proxy.</p></li><li><p><strong>Request Duration</strong> (<code>istio_request_duration_seconds</code>): This is a <code>DISTRIBUTION</code> which measures the duration of requests.</p></li><li><p><strong>Request Size</strong> (<code>istio_request_bytes</code>): This is a <code>DISTRIBUTION</code> which measures HTTP request body sizes.</p></li><li><p><strong>Response Size</strong> (<code>istio_response_bytes</code>): This is a <code>DISTRIBUTION</code> which measures 