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[[File:RPS logic.png|upright=1.7|thumb|Diagram showing how RPS load balance incoming packets across the CPU cores]]
Receive Packet Steering (RPS) is the RSS parallel implemented in software. All packets received by the NIC are load balanced between the cores' queues by implementing an hash function using as configurable key the header fields (like the layer 3 source and destination IP and layer 4 source and destination ports), in the same fashion as RSS does.
Moreover thanks to the hash properties, packets belonging to the same flow will always be steered to the same core. <br>
This is usually done in the kernel, right after the NIC driver. Having handled the network interrupt and before it can be processed, the packet is sent to the receiving queue of a core, which is then notified thanks to an inter process interrupt. <br>
RPS can be used in conjunction with RSS, in case the number of queues managed by the hardware is lower than the number of cores. In this case after having distributed across the RSS queues the incoming packets, a pool of cores can be assigned to each queue and RPS will be used to spread again the incoming flows across the specified pool.<ref name="RPS linux news (LWM)" /><ref name="RPS by redhat" /><ref>{{Cite web|title=RPS kernel linux docs|url=https://www.kernel.org/doc/html/v5.1/networking/scaling.html#rps-receive-packet-steering|access-date=2025-07-08|website=kernel.org|publisher=The Linux Kernel documentation|language=en-US}}</ref>
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