This is the 64-bit version of cefPrefixPkts, tracking the same per-prefix packet count under per-prefix CEF accounting but without the 32-bit counter's risk of wrapping on a high-traffic prefix. On a busy core prefix moving tens of millions of packets per minute, the 32-bit cefPrefixPkts could wrap in well under an hour, so this 64-bit counter is the one an admin should actually poll for accurate long-interval traffic totals on high-volume destinations. A heavily-trafficked transit prefix moving 40 million packets per minute would wrap a 32-bit counter in under two minutes, making this 64-bit version the only reliable choice for accounting over any longer polling interval.