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* 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.
* Put the links and the crypto they use in link/, a part of their owneunhhu2026-09-292-7/+8
| | | | | libpure-link.a holds them; pure-serve and the M5 harness link it instead of naming its source files.
* Measure the drains again with the outbox as a list (096)eunhhu2026-09-291-0/+18
| | | | | | | Between two pure-serve nodes, 16 KiB records drain at 33,600 a second (23,000 before), the links spending 58 us a record (76), under quinn's 60 while the receiver also stores each one. 1,013 bytes: 406,000 a second (347,000). Saving sends one by one: 5,000 of 16 KiB in 0.91 s (84.8).
* Measure the CPU a record costs a link, against quinn (096)eunhhu2026-09-294-21/+267
| | | | | | | | | | | | | | | | | | | | | M5 of design 011. At first a link spent eight times quinn's CPU on a small record: scans of the backlog, a system call and allocations a record, 19 bytes of framing. After the seven changes before this one, the transport alone (transport.c; a backlog drained, every record checked) spends per record 0.30 us for 61 bytes (quinn 0.27: 1.06 to 1.12 times over three campaigns, at the design's 10 % line), 2.91 us for 1,013 bytes (quinn 3.88) and 45.2 us for 16,013 bytes (quinn 60.9): 25 % less for the larger ones, and 30 % more records a second. What is left for small records is per packet: the stream's names and the RECORDS head. quinn's numbers carry no confirmation of storing and no exactly once. Between two pure-serve nodes the links spend more per record, woken at the receiving app's pace. Filling the sender showed the outbox is written whole at every save, as the numbers heard were (094): the next thing to change. run.py gains --transport and --drain; the quinn service reads a drain a chunk at a time and its client writes 64 KiB at a time.
* 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.
* Measure a restart under load and a first contact (095)eunhhu2026-09-286-25/+201
| | | | | | | | | | | | | | | | | | M2 and M4 of design 011. Ten thousand devices send an order every five seconds (2,000 a second); the receiver is killed (-9) at about 21 s and started again at once. With its secrets remembered the node shows no 100 ms step without an order stored, catches up in 0.2 s, spends no more CPU than before and makes no X25519; 34 orders were sent again, and every order made was applied once (three rounds; on the SD card the same, with 0.2 s silent). Without the memo it makes 10,000 X25519, 1.6 s of CPU. quinn under the same load stops for 1.0 s and catches up after 10.9 s: 10,115 new connections, about 7 s more of the service's CPU and 8 s of the clients'. A first contact takes Pure one round trip and QUIC two, at 10, 50 and 100 ms of RTT. run.py --restart and --first-contact make them; the quinn harness gains a fixed port with a reset key from its key, clients that connect again, and a drain for M5.
* Measure a link at rest: 132 bytes against a QUIC connection's 38,106 (094)eunhhu2026-09-287-0/+1974
M1 of design 011. A Pure node allows 1,000 to 1,000,000 senders; each sends one order and, once told it is stored, rests. At rest a link costs the node 132 bytes (the sender allowed, 73; its number heard, about 60) and no transport state; with a million the node runs in 139 MB. A quinn 0.11 service holding the same exchange's clients connected at rest costs 38,106 bytes a connection: 289 times as much, past the design's 1/100. A link at rest takes its next record in 0.56 ms to stored, one X25519 on the node included; a new QUIC connection takes 1.06 ms and 2.8 times the receiver's CPU, without storing. research/experiments/019-idle-links: links.c, many senders written from serve/link.h's packet format alone (a second implementation), and the quinn service and clients (quic/, built offline); run.py makes both measurements.