Lines Matching refs:packets

24 (multi-queue). On reception, a NIC can send different packets to different
25 queues to distribute processing among CPUs. The NIC distributes packets by
43 Some advanced NICs allow steering packets to queues based on
44 programmable filters. For example, webserver bound TCP port 80 packets
69 this to notify a CPU when new packets arrive on the given queue. The
129 RPS may enqueue packets for processing. For each received packet,
134 packets have been queued to their backlog queue. The IPI wakes backlog
135 processing on the remote CPU, and any queued packets are then processed
148 (the default), in which case packets are processed on the interrupting
169 reordering. The trade-off to sending all packets from the same flow
177 during CPU contention by dropping packets from large flows slightly
182 count over the last 256 packets. If a flow exceeds a set ratio (by
183 default, half) of these packets when a new packet arrives, then the
186 No packets are dropped when the input packet queue length is below
228 While RPS steers packets solely based on hash, and thus generally
232 kernel processing of packets to the CPU where the application thread
234 to enqueue packets onto the backlog of another CPU and to wake up that
237 In RFS, packets are not forwarded directly by the value of their hash,
242 If an entry does not hold a valid CPU, then packets mapped to that entry
254 receive packets on the old CPU, packets may arrive out of order. To
255 avoid this, RFS uses a second flow table to track outstanding packets
258 counter. The CPU index represents the *current* CPU onto which packets
262 recently migrated a userspace thread while the kernel still has packets
274 And now the trick for avoiding out of order packets: when selecting the
290 there are no packets outstanding on the old CPU, as the outstanding
291 packets could arrive later than those about to be processed on the new
329 the application thread consuming the packets of each flow is running.
330 Accelerated RFS should perform better than RFS since packets are sent
337 queue for packets matching a particular flow. The network stack
340 method to program the NIC to steer the packets.
392 This transmit queue is used for subsequent packets sent on the flow to
393 prevent out of order (ooo) packets. The choice also amortizes the cost
394 of calling get_xps_queues() over all packets in the flow. To avoid
395 ooo packets, the queue for a flow can subsequently only be changed if
397 there are no outstanding packets in the flow, so the transmit queue can
398 change without the risk of generating out of order packets. The