Routers with network processing unit and central processing unit-based line cards

A method comprising:

• receiving, by a processor, utilizations of a first set of entries in a forwarding table of a central processing unit-based line card of a router;
• receiving, by the processor, utilizations of a second set of entries in a partial forwarding table of a network processing unit-based line card of the router, wherein the second set of entries comprises a subset of the first set of entries, wherein the second set of entries comprises entries that are most utilized by a plurality of line cards of the router, the plurality of line cards including the central processing unit-based line card and the network processing unit-based line card, wherein the central processing unit-based line card and the network processing unit-based line card are distinct physical devices, wherein the network processing unit-based line card is configured to forward a packet received at the router to a destination when an entry in the partial forwarding table of the network processing unit-based line card matches the packet and to transfer the packet to the central processing unit-based line card to allow the central processing unit-based line card to forward the packet to the destination using the forwarding table of the central processing unit-based line card when there is no entry in the partial forwarding table of the network processing unit-based line card that matches the packet;
• and
• updating, by the processor, the second set of entries in the partial forwarding table to comprise the entries that are the most utilized by the plurality of line cards of the router.

A device comprising:

• a processor;
• and
• a computer-readable medium storing instructions which, when executed by the processor, cause the processor to perform operations, the operations comprising:
• receiving utilizations of a first set of entries in a forwarding table of a central processing unit-based line card of a router;
• receiving utilizations of a second set of entries in a partial forwarding table of a network processing unit-based line card of the router, wherein the second set of entries comprises a subset of the first set of entries, wherein the second set of entries comprises entries that are most utilized by a plurality of line cards of the router, the plurality of line cards including the central processing unit-based line card and the network processing unit-based line card, wherein the central processing unit-based line card and the network processing unit-based line card are distinct physical devices, wherein the network processing unit-based line card is configured to forward a packet received at the router to a destination when an entry in the partial forwarding table of the network processing unit-based line card matches the packet and to transfer the packet to the central processing unit-based line card to allow the central processing unit-based line card to forward the packet to the destination using the forwarding table of the central processing unit-based line card when there is no entry in the partial forwarding table of the network processing unit-based line card that matches the packet;
• and
• updating the second set of entries in the partial forwarding table to comprise the entries that are the most utilized by the plurality of line cards of the router.