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* Push a turn's sends to a link at once, and round only the links that want ↵eunhhu2026-10-011-1/+3
| | | | | | | | | | | | one (017, 2b-1) The sending loop was woken by every record queued while it slept: the owner queues one by one, the loop caught up and slept between them, and every link took a round on every wake. Four links sent 64k packets of 12 records where threads sent 40k of 20, and ran at 257k sends/s against 581k. The owner now queues a turn's sends and pushes each link once; the loop rounds a link only when its socket has answers, it was pushed, or its time came.
* Queue only the way to the receivers behind M6's bottleneckeunhhu2026-09-291-3/+4
| | | | | | | | tbf with netem under it lost tbf's queue (netem became it), and the answers queued behind the data. Now each way has its netem, the way to the receivers' ports then a tbf whose queue holds a round trip; the way back does not queue. transport.c takes its listener's port (TRANSPORT_PORT).
* Apply a link's records in transport.c as a host doeseunhhu2026-09-291-11/+20
| | | | | | From the one after the last heard, letting be the ones heard before and stopping at a gap: the listener's first delivery may begin past it when packets reorder, which the harness counted as wrong.
* Measure a link on a path of loss, reordering and a bottleneck (M6 harness)eunhhu2026-09-291-18/+62
| | | | | | | | | 020-lossy-paths/run.py runs each case in an unprivileged namespace: a 50 Mbit/s tbf bottleneck under netem's delay, jitter and loss, both ways. A link may send without UDP GSO (pure_link_gso), as netem takes a burst as one packet; quinn the same (QUIC_GSO=0). transport.c and the quinn harness give the records handed over in each 100 ms, and at a steady rate the time each took; TCP CUBIC flows run beside them.
* Keep a link's two sides as state alone, the sockets and threads aparteunhhu2026-09-291-3/+3
| | | | | | | | | | | | link/link-protocol.h is the protocol with no socket, thread or clock of its own: packets and time in, packets out. link/link.h carries it over UDP as before. A sender starts small (8 flights, 16 records, a 4 KiB ring) so one thread can hold many. The transport's CPU a record is the same within 2% (five rounds each way, 61 B to 16 KiB). test-link runs both sides through a network of its own: loss, packets held back and doubled, failed saves, an idle sweep, and both sides starting again, every record applied once as sent.
* Let links know nothing of the core: the host names inputs and shapeseunhhu2026-09-291-6/+15
| | | | | | A sender takes its messages' shape, and a listener asks its host which input a stream goes to. The core gives the shape (pure_module_shape); link/ now builds without the core's headers.
* Send a record whole when it fits a packet, however many pieces it haseunhhu2026-09-291-6/+20
| | | | | | | | | | | | | | | | | A record over a piece (1,000 bytes) went in pieces even when it fit the packet whole: a record of 1,013 bytes went as two RECORD frames, and the receiver gathered it the slow way (an allocation, pieces, then onto the line). A record none of whose pieces went yet now goes whole in a RECORDS frame whenever it fits what is left of the packet; its pieces are marked sent together. A record too large for a packet, or one resent after some of its pieces were lost, still goes in pieces, and a receiver takes a record whole or in pieces alike. The transport alone takes 2.85 us a record of 1,013 bytes, not 3.18 (quinn: 3.90). transport.c now checks every record delivered: in order, once each, its bytes as sent. None was wrong in a network namespace with 1 ms of delay, 3 % loss and 10 % reordering, with records of 61, 1,013 and 16,013 bytes.
* Wake a link's thread only when it sleeps, onceeunhhu2026-09-281-0/+165
Every queued record wrote the link's eventfd, a system call each, and woke the thread to send a packet of a few records. A record queued now wakes the thread only when it sleeps and nobody woke it yet; one queued while it sends marks the link, and the thread looks again before it sleeps. With records queued one at a time as fast as a thread can, 200,000 small ones went at 400k a second, and now at 730k; queuing one costs 0.43 us, not 1.0. research/experiments/019-idle-links/transport.c measures the transport alone: a link and a listener in one process, no app, no store. A backlog of 200,000 records of 61 bytes drains at 3 to 4 million a second, 0.24 us a record on each side.