Lines Matching +full:packet +full:- +full:based
1 .. SPDX-License-Identifier: GPL-2.0
14 http://oss.oracle.com/pipermail/rds-devel/2007-November/000228.html
22 cluster - so in a cluster with N processes you need N sockets, in contrast
23 to N*N if you use a connection-oriented socket transport like TCP.
25 RDS is not Infiniband-specific; it was designed to support different
29 The high-level semantics of RDS from the application's point of view are
39 transport has to be IP-based. In fact, RDS over IB uses a
59 a active-active HA scenario), but only as long as the address
72 to create RDS sockets. SOL_RDS is the socket-level to be used
87 This is a soft limit rather than a hard limit - RDS will
105 return with -EMSGSIZE
141 a destination marked congested - in this case you will loop
144 this - by using congestion notifications, and by checking for
175 see rds-rdma(7) manpage (available in rds-tools)
194 per-packet sequence number
196 piggybacked acknowledgment of last packet received
208 ACK_REQUIRED receiver must ack this packet
209 RETRANSMITTED packet has previously been sent
222 passing RDMA-related information.
232 if another HCA is available for fail-over.
237 packets. Ack-only packets are reduced by only allowing one to be
244 RDS's IB transport uses a credit-based mechanism to verify that
255 should return block or return -EWOULDBLOCK.
259 "back-pressure" is considered a bug.
270 is much easier to implement than some finer-grained
271 communication of per-port congestion. The sender does a very
279 As mentioned above, RDS is not IB-specific. Its code is divided
295 be sent and sets header fields as needed, based on the socket API.
303 code to handle the actual copy-to-user.
306 per-socket information
309 per-connection information
312 pointers to transport-specific functions
315 non-transport-specific statistics
328 then maintained forever -- if there are transport errors, the
329 connection will be dropped and re-established.
332 partially-sent datagrams to be retransmitted when the connection is
333 re-established.
340 - struct rds_message built from incoming data
341 - CMSGs parsed (e.g. RDMA ops)
342 - transport connection alloced and connected if not already
343 - rds_message placed on send queue
344 - send worker awoken
347 - calls rds_send_xmit() until queue is empty
350 - transmits congestion map if one is pending
351 - may set ACK_REQUIRED
352 - calls transport to send either non-RDMA or RDMA message
356 - allocs work requests from send ring
357 - adds any new send credits available to peer (h_credits)
358 - maps the rds_message's sg list
359 - piggybacks ack
360 - populates work requests
361 - post send to connection's queue pair
367 - looks at write completions
368 - unmaps recv buffer from device
369 - no errors, call rds_ib_process_recv()
370 - refill recv ring
373 - validate header checksum
374 - copy header to rds_ib_incoming struct if start of a new datagram
375 - add to ibinc's fraglist
376 - if competed datagram:
377 - update cong map if datagram was cong update
378 - call rds_recv_incoming() otherwise
379 - note if ack is required
382 - drop duplicate packets
383 - respond to pings
384 - find the sock associated with this datagram
385 - add to sock queue
386 - wake up sock
387 - do some congestion calculations
389 - copy data into user iovec
390 - handle CMSGs
391 - return to application
395 Mprds is multipathed-RDS, primarily intended for RDS-over-TCP
397 implementation of RDS-over-TCP is implemented by demultiplexing multiple
402 (a) upper-bounded to the single-flow bandwidth,
403 (b) suffers from head-of-line blocking for all the RDS sockets.
405 Better throughput (for a fixed small packet size, MTU) can be achieved
408 connection. RDS sockets will be attached to a path based on some hash
414 a common (to all paths) part, and a per-path struct rds_conn_path. All
422 transport is multipath-capable, rds_sendmsg() hashes outgoing traffic
423 across multiple paths. The outgoing hash is computed based on the
430 This is done by sending out a control packet exchange before the
431 first data packet. The control packet exchange must have completed
435 The control packet is an RDS ping packet (i.e., packet to rds dest
436 port 0) with the ping packet having a rds extension header option of
438 number of paths supported by the sender. The "probe" ping packet will
442 sent in response to a probe-ping should contain the rcvr's npaths
443 when the rcvr is mprds-capable.
445 If the rcvr is not mprds-capable, the exthdr in the ping will be
447 of the probe-ping can default to single-path mprds.