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* Record queries on the bank beside SQLite (091)eunhhu2026-09-281-0/+110
| | | | | | | | | | | | 091 measures four queries on pgbench's tables of 100,000 accounts, the same rows and answers on Pure (registered queries, HTTP and JSON included) and SQLite 3.46.1, through each step: items field by field in leaves, folds and filters a leaf at a time, and one pass answering a fold in a column for every row. Per-branch totals went from 398 ms to 4.9 ms (SQLite 45, 14.3 with a DBA's indexes), a three-table join from 3.3 to 0.48 ms (1.47), and each rich account's rank from 9.2 s to 6.8 ms (2.84 s, 7.6 ms with an index); counting accounts in credit takes 1.05 ms where an index lets SQLite count 0.16 ms. Pure declares no index.
* Run pgbench's transaction on a bank of 100,000 accounts, beside SQLite (090)eunhhu2026-09-271-0/+99
| | | | | | | | | | | | | | | | | benchmarks/bank/bank.aup keeps accounts, tellers and branches as keyed lists and a history list; a transfer changes a row of each and appends a history row in one event, as pgbench's TPC-B-like transaction does in SQL. run.py makes a scale's rows and drives transfers through the load generator's new transfer kind; sqlite-bank.c runs the same tables and SQL on SQLite 3.46.1, a connection a thread, WAL. With lists as trees, transfers run at 30.5k a second on 1,000 accounts and 24.5k on 100,000 (RAM store, one connection thread, HTTP and JSON included), where they ran at 3.2k on 30,000 before. Durable on the SD card, Pure makes 1,339 a second and SQLite with synchronous=FULL 84 to 153. SQLite in process with no HTTP makes about 40k in RAM: recorded as it is, with the write amplification of 100,000-row tables on the card and ad hoc queries as what comes next.
* Record the messenger between two nodes and its latency (089)eunhhu2026-09-271-0/+80
| | | | | | | | | | | | | | The roadmap's E2EE messenger made of the runtime's general parts, with no messenger code in it: sealed, authenticated sessions between nodes (086, 088), Vega on each node's display as a surface (design 010), the app in Vega's examples. Vega's check runs two nodes through a recording relay: a line typed on one display is drawn on the other, frames match the vega command's, and the relay sees no text. A line takes 0.79 ms at p50 and 1.1 ms at p99 from one node's program to the other node's views with stores in RAM, both commits, the HTTP delivery and the seal included (sealing adds nothing measurable); on the Pi's SD card 3.5 ms at p50, the long tail being the card's syncs.
* Seal in one session a wire, authenticated by the sender's key (088)eunhhu2026-09-271-0/+83
| | | | | | | | | | | | | | | | | | | | | | A sealed request cost three X25519 operations (about 0.5 ms), so sealed sends drained at half the plain rate. A wire now keeps one HPKE context, encapsulated at its first seal, and seals each request as the context's next number (a failed seal or a restart starts a new session); the header carries the session's encapsulated key and the number, so a receiver opens a session once per connection thread (16 remembered, the least used replaced) and each seal by its number, also after it restarts, unasked. A sender with a key of its own seals in HPKE auth mode and names that key in the header; a receiver started with --sender NAME=KEY takes deliveries only from the senders it names, each sealed with its key (403 sender otherwise). The body is now the ciphertext and its tag. Sealed sends, sender authenticated, drain at 461-464k a second against 462-470k plain and 207-234k sealed a request at a time (Raspberry Pi 5). The check adds: a wire's requests share one session numbered from 0; a changed number or sender key does not open; a receiver restarted naming its sender opens the same session again; another node claiming that sender's name with its own key is refused and applies nothing.
* Record the small reads and idle memory work, next to axum and drogon (087)eunhhu2026-09-271-0/+120
| | | | | | | | | | | | What the app model, snapshot reads and delivery had cost small reads (126.7k -> 116.1k GETs a second) and idle memory (2.0 -> 4.5 MiB), how the sampler found it, and the four steps and the crypto split that took it back: 139.9k and 2.3 MiB. Measured again today beside axum 0.8.9 and drogon 1.9.0 on the same Pi: a one-thread pure-serve answers small GETs at 139k/s (2.2x axum and drogon a CPU second), 1 MiB GETs at 2,362/s (axum 1,304, drogon 754), durable app writes at 21.3k/s (both about 200), with the least idle memory of the three.
* Seal delivered sends to the receiver's key (086)eunhhu2026-09-271-0/+96
| | | | | | | | | | | | | | | | | | | | --seal OUTPUT=KEY seals each request's body whole to the receiving node's public key with HPKE (RFC 9180, base mode: X25519, HKDF-SHA256, AES-128-GCM where the CPU has AES, else ChaCha20-Poly1305), bound to the request's source, first number and count; X-Pure-Seal names the suite. A receiver's --key is a raw 32-byte file, made 0600 when missing, held in OpenSSL's secure heap; it opens the body where it lies (400 seal when it does not open) and zeroes the plain text when the request's ticket goes. --sealed-only refuses unsealed deliveries (403 unsealed). The check puts a recording relay between two apps: every order applies once, no body shows an item or a field name, a flipped bit is refused, a replayed request applies nothing twice, and a seal to another key does not open. Its hosts choose their own ports (--port 0). Sealed sends drain at 233-235k a second against 469-470k plain (Raspberry Pi 5): three X25519 operations a request, 164 us each. The plain request path measured the same as before.
* Give a compacted file the zeros of its whole cycle (085)eunhhu2026-09-271-0/+62
| | | | | | | | | | | | | | | | Commits grew the tree store's tail 256 KiB at a time, each growth a sync that also committed the ext4 journal for the new size and blocks. A file installed by compaction now carries written zeros up to where the next compaction will come (4 x live + slack, plus a commit's margin), capped at the size of the file it replaces, so a store never takes more space than before and shrinks when its live data does. The cycle's commits then only overwrite blocks the file has. Store commits: 317.5 -> 385.5 a second, ext4 journal commits 109 -> 45 for 4,000 commits; durable app posts +5.3%, their p99 the same within this SD card's noise. The new cycles test keeps sizes still between compactions once the live data is whole, and shows the file shrinking with it.
* Measure what moving saves off the owner would buy (084)eunhhu2026-09-271-2/+30
| | | | | | | | | | | | Nothing a thread can give: with writes saturated the device's one line of syncs is the bottleneck, so zeroing the tail or compacting on another thread only queues that device work behind the commits, and the owner's idle gap is shorter than one journal commit. Built without compaction the store is no faster; without compaction and without tail growth durable posts gain 1.4% and the p99 drops 24% (17.4 to 13.3 ms). New blocks are the tail latency, so the way to it is a store that rewrites its space in place, a ring cleaned forward instead of compacted into new files.
* Measure whether sharding owners by key would add writes (084)eunhhu2026-09-271-0/+47
| | | | | | | | | | | It would not, on this device. One file's syncs or four at once, the SD card completes the same 510-690 commits per second, the latency growing with the number of files. The scoreboard app with two owners, each with a store of its own, took 23% fewer durable posts than one owner (median 16,230 against 20,974 a second) with 2-3x the p99: syncs queue, and each carries half the events. One owner's group commit stays; cores serve reads, and writes grow by making the sync itself cheaper.
* Check pure-serve in Pure, not in aupeunhhu2026-09-275-7/+7
| | | | | | | | | | The HTTP host's end-to-end checks (documents against the earlier server, lending, kill -9 durability, JSON, timers, links, webhooks and answers) sat in aup's tests, so a change to the host was verified from the toolchain. They now live in tests/check.py; make check builds their apps with the sibling aup and runs them after the unit tests, which stay beside their parts. Design 009 states the rule for all three repositories.
* Lay Pure out as a core with the parts selected around iteunhhu2026-09-279-10/+10
| | | | | | | | | | | | | | | | | | | | | The app model, the tree store and the HTTP host lived in prototypes/connections among the earlier document runtime, the store was known only by its format's name, and Vega compiled six Pure sources by path. Now, as the README's principle has it: core/ runtime, flow and the app model (module*.c), with what the core asks of storage (state.h, store.h) store/ the tree store (PURETRE3, PUREREC1) serve/ pure-serve: HTTP host, outbound delivery, JSON in place cli/ pure-run, pure-edit-module A top-level make builds libpure.a (app model and store, for hosts to link) and the hosts; make check runs the store's and the app model's tests. The earlier runtime still builds from prototypes/connections against core/ and store/ (check, check-tree and check-core pass). Design 009 records the rule: parts by role behind libraries; git repositories split by coupling, so the store stays here while its contract moves with the core, and Vega stays apart.
* Look for new sends newest first, only as far back as they goeunhhu2026-09-271-2/+2
| | | | | | | | | After each save the owner walked the whole outbox to find the sends not yet queued, so a receiver long down made every save walk the backlog. pure_app_outbox_newest visits saved sends newest first, and the owner stops once every wired output reaches the number it queued last, then queues what it found in order.
* Make an API's answers the app's events (--reply OUTPUT=INPUT)eunhhu2026-09-271-2/+22
| | | | | | | | | | | | | | | | | | | | | The final answer to each send of a wired output (a 2xx, or a 4xx but 408 and 429) becomes a message event of the given input: fields from the answer's JSON object by name, other members skipped; a field the answer lacks from the send's field of that name and type, so the request's own id is there; a u32 http_status field is the status. It is applied with the send's number from the wire's source, before the send is trimmed and in the same save, so an answer that comes again after a restart (the API repeating itself for the Idempotency-Key) applies once. Sends that wait for answers go one per request; answers are saved with the next round, or at once when none waits. A server that writes an answer in pieces holds the second until the first is acknowledged, and a delayed acknowledgement stalled every answer 40 ms: the client now acknowledges at once (TCP_QUICKACK) after each read. Against a payments API that answers 200 or 402, with the sender killed (-9) midway, paid and declined orders matched the API's answers one to one.
* Deliver to https receivers, verifying their certificates (083)eunhhu2026-09-271-3/+6
| | | | | | | | | | A wire to an https:// URL speaks TLS 1.2 or later through OpenSSL: the receiver's certificate must chain to the system's CAs (or to the file --send-ca names) and name its host (SNI and SSL_set1_host, or the IP address). An untrusted receiver gets nothing: the send stays in the outbox, the wire logs it and tries again every 10 s. pure-serve now links libssl and libcrypto.
* Deliver an app's saved sends over HTTP, in order and in batches (083)eunhhu2026-09-272-2/+75
| | | | | | | | | | | | | | | | | | | | pure-serve --send OUTPUT=http://host:port/path wires an output: after every save the owner queues the new sends as JSON (fields and groups) and a thread per output posts them in order with X-Pure-Source, X-Pure-Sequence and Idempotency-Key. A 2xx, or a Pure receiver's refusal, delivers; the owner then trims. 408, 429, 5xx and no answer are sent again after a pause growing to 10 s, other answers every 10 s: nothing is dropped. A Pure receiver applies a delivered message with pure_app_deliver (now taking placed fields) and advertises X-Pure-Batch: 256; the sender then posts up to that many numbers in a row as one JSON array (X-Pure-Count), applied in order in one burst with one save. Delivery kept up with orders once batched (391 deliveries/s one at a time; a backlog of 20,000 went at 60k/s). With four clients ordering, killing the receiver and then the sender (-9) left the receiver's count and total equal to what the sender saved, five times and under ASan.
* Send messages as part of events and apply delivered ones once (078)eunhhu2026-09-271-3/+4
| | | | | | | | | | | | | | | | | | | | | | | An output (input kind 5) is a message the app sends; SEND (72) takes an output's field values in order in a handler, lays them out as a message's payload and keeps it, numbered per output from 1, with the event's changes: a failed event sent nothing, and a failed save takes back every send since the last save with its numbers. A host sees only saved sends (pure_app_outbox) and trims what its receiver has saved (pure_app_trim, gone with the next save). pure_app_deliver applies a message from a named source once: a number heard before succeeds without applying, a refused message counts as heard, a failed save forgets what it heard. Sends, numbers and heard numbers are the app's links state, stored whole in one runtime document (PLK1) with the states, in the same commit. Outputs follow their names across module changes; a module that drops or retypes an output with sends left is refused, and a dropped output's number is kept for when it returns. Killing the process at every commit stage leaves an event and its send, or a delivery and its effect, together or neither. pure-serve answers a post to an output or a timer with 404 no_input.
* Record the bound of taking tail growth and compaction off commits (081)eunhhu2026-09-271-3/+5
| | | | | | | Measured with a build that grows its tail by 64 MiB once and never compacts: durable posts +5-8% (64 connections), p99 about halved; the slow syncs that remain come from the device.
* Read JSON bodies in place, groups included (082)eunhhu2026-09-271-0/+78
| | | | | | | | | | | | | | | | | | | | | pure-serve no longer copies a JSON body's strings into the message's payload. The ingress is the prefix, a table of each field's start and size, and the body as it came; the connection thread scans the body once, puts numbers into the prefix and records where each string is. Only a string with escapes is unescaped, over itself (it never grows). A group of fields comes as an object inside the body and, for a fixed field, as its path in the query (?to.zip=7). A group where a field belongs, a value where a group does, an array or true/false/null is json_type; an unknown member, inside a group too, json_field. The string scan and UTF-8 checks now pass over eight bytes at a time while none needs a look (pure_utf8_step, so every text check gains). On the Pi, posting {"name":"k","text":"x..."} to a stateless app went from 652-655 to 3,737-3,953 requests/s with 256 KiB of text (server CPU 1.52 to 0.25 ms a request, peak RSS 5.2 to 3.2-3.4 MiB) and from 29.1k to 76.3-76.7k/s with 4 KiB; the load generator gains a json method and benchmarks/http/echo.aup is the app.
* Write each commit's head just before its bytes: one range per sync (081)eunhhu2026-09-261-0/+104
| | | | | | | | | | | | | | | | | | | | | | | A tree store commit wrote its bytes over the written zeros of the tail and its head into a slot at the start of the file: two ranges, and on the Pi's SD card a sync of two ranges costs about twice one (2.4 ms against 1.2 ms). A commit now writes a 128-byte record (its head) at the published end and its bytes right after it, then syncs once. Every 16 commits the head also goes into the older slot. The newest commit is found from the newer slot's head, or from the newest head this process has seen in the file while its record is still there, along the records whose bytes are whole; a torn record or bytes end the walk at the commit before, which the next writer overwrites. Slots of this format are PURETRE3; files of the earlier one are read and continued. Store commits went from 220-233/s to 371-396/s (p50 2.5 to 1.3 ms), and the scoreboard's durable posts from 13-16k/s to 21-26k/s with 64 connections and from 2.2-2.4k/s to 2.9-3.9k/s with 8, measured alternately with the previous build. The torn head check now tears a slot (the walk goes on from the other) and the newest record (a new process sees the commit before); a new check walks 42 commits from the slots, in a fresh process too, and stops at a damaged record.
* Show views from the last save's snapshot on connection threads (080)eunhhu2026-09-261-0/+135
| | | | | | | | | | | | | | | | | | | | The owner publishes a snapshot of the saved states after every save, before it hands back the answers; connection threads take the newest one each round and show views from it with a reader app of their own. A read made after a write's answer sees the write, nothing unsaved or undone is ever shown, and reads no longer wait while the owner applies events or syncs. Apps with states always get an owner thread, even with one connection thread. A round's inputs go to the owner first; its views are shown and then answered together (answering each one as it was shown made one thread's 20-row page 8% slower). On the Pi 5, with 8 connections posting durable scores and 56 reading the total, reads went from 10-16k/s at p99 13-29 ms to 107-149k/s at p99 0.6-0.7 ms, and posts stayed in range; axum and drogon, which sync under their lock, read 1.1-1.3k/s at p99 111-156 ms. A snapshot of a changed 1,024-item list costs 1.2 us (65,536 items: 87 us) against a 3-4 ms save.
* Lend a text state's stored extents for its view (079)eunhhu2026-09-261-0/+52
| | | | | | | | | | | | A view that shows a text state as it is (pure_module_text_state) now goes out as the state's stored extents, as a document read does: the answer holds the store mapping, charged to the budget, until it is sent and its ticket released; a state with edits not yet stored is copied as before. Documents and views share one loan path, and the extent array grows as needed. A 1 MiB note read by 8 connections: 776-817 answers a second copied, 1,875-1,901 lent, p50 9.2 to 3.5 ms, peak RSS 10.3 to 5.7 MiB. The load generator learns GET /views/page.
* Design connections between apps (078), not yet builteunhhu2026-09-261-0/+80
| | | | | | | | | | A sent message belongs to its event's transaction in a runtime-owned outbox; hosts deliver committed messages in order, and a receiver keeps the last sequence per source in the same commit, so the effect is exactly once. The note records the design and its order of work; it waits behind the roadmap's short-term items and goes with outbound calls, which stand on the same outbox.
* Record the app service against axum and drogon (077)eunhhu2026-09-261-0/+93
| | | | | | | | | | | | The scoreboard, 22 lines of aup served by its views and inputs, against the same service written by hand in axum and drogon on the Pi: durable posts about 76 times as many, reads level with drogon and ahead of axum with the least CPU and memory. The note keeps what the profile showed on the way (the kernel's share of a single thread, integers through printf, an owner that saved too early) and what comes next. run.py gains pure-serve-2 and waits for a server that prints its port before it listens.
* Record why the remaining store ideas waiteunhhu2026-09-261-3/+16
| | | | | | | | | | | The zero tail wrote as many bytes as the commits under 64 writers, yet turning it off changed nothing beyond the SD card's own noise and made 8 writers wait longer, so it stays until faster storage is measured. Overlapping a sync with the next burst would win a few percent at most. The second sync of a new process's first commit is rare with one owning server. The larger lever is write amplification: a 16-byte edit rewrites its whole leaf and catalog path.
* Compare the HTTP host with drogon and by CPU timeeunhhu2026-09-261-0/+36
| | | | | | | | | | | | | | | | | A drogon 1.9 service with the axum baseline's contract joins the benchmark (memory, fdatasync and crash-safe modes, three IO threads), built from Debian's packages unpacked under .deps without installing them. drogon listens once per event loop, so the service picks a free port itself: with port 0 every loop got a port of its own and the load reached one. The load generator has one core and saturates near 150k answers a second, so the harness now also reports answers per second of server CPU time (all threads). Over three rotated rounds: small GETs 151.6k/s on three shards (drogon 145.3k, axum 120.9k) and 128k per CPU-second on one thread (drogon 65k, axum 62k); 1 MiB GETs 2,794/s (axum 1,372, drogon 708); crash-safe PUTs 5.1-5.8 times axum and 13-30 times drogon; peak RSS 5.0 MiB against 14.4 and 76.5 MiB. --workloads is now a regular expression.
* Make a tree store commit durable with one synceunhhu2026-09-263-1/+160
| | | | | | | | | | | | | | | | | | | | | | A commit used to sync its nodes, then write the head and sync again: the order of writes was forced by syncs. Now the head carries where the commit's bytes start and their digest, and one fdatasync makes the bytes and the head durable together. A crash during it can leave a head whose bytes did not all reach the device; its digest then fails and the older slot stands, which is safe because a writer only builds on a durable head. Commits overwrite written zeros kept after the published end, so the sync changes neither the size nor the block map and needs no journal commit. On the SD card this is 2.4 ms per commit against 9.1 ms for two syncs; the store commits 289-304 times a second instead of 94-109, and pure-serve answers 2,012-2,611 durable PUTs a second against 583 for crash-safe axum. A process remembers the heads it published or checked, so it reads a commit's bytes at most once and never its own. Its readers pass over the head it is still making durable and so never answer with a commit a crash could take back. Head slots get a block each and the format becomes PURETRE2; a handle's refresh reads the slots through its mapping.
* Lend stored extents to reads instead of copying themeunhhu2026-09-261-0/+22
| | | | | | | | | | | | | A read of a stored document now answers with the store mapping's extents through writev, without copying the document. pure_draft_mapping takes a reference to the mapping a draft opened through a handle reads from; the answer keeps it until the last byte is sent, so the version read goes out intact even if the document changes or a compaction replaces the file meanwhile. Replies the mapping does not hold are copied as before. pure-serve's output is now a list of extents (the head first). One thread serves 2,761 1 MiB reads per second (axum: 1,380) and 128k small ones.
* Shard pure-serve across coreseunhhu2026-09-261-0/+27
| | | | | | | | | | | | | | | | | | A burst now looks at the store once (pure_store_pin) instead of once per request; another shard's commit ends before its answer is sent, so a request made after that answer still reads it. With this alone one thread serves 125k small keep-alive reads per second, as many as axum on three cores, with a shorter p99. --threads N runs a shard per thread: its own SO_REUSEPORT listener, epoll set, runtime domain, app and store handle. Writer sessions of the tree store now take turns inside a process with a mutex (the file lock belongs to the process and does not keep threads apart), and revisions settle concurrent edits of a key. A module with states runs on one thread. Three shards serve 151k reads per second; they still commit one by one, so durable writes and 1 MiB reads are better on one thread for now, which stays the default. Note 075 records the numbers.
* Serve modules over persistent connectionseunhhu2026-09-261-0/+23
| | | | | | | | | | | | | | | | pure-serve replaces the module mode of server.c, which goes back to what it was. It keeps the document contract, the runtime core (a work slot per connection, the payload budget, core-owned ingress, borrowed PUT replies) and the group commits, and adds what server.c lacked: HTTP/1.1 persistent connections with in-order pipelining, an edge-triggered epoll owner thread, up to 1,024 connections allocated as they arrive and reused, one writev per answer, and documents opened through a store handle. On the Pi 5 with one thread it serves 106k small keep-alive reads per second (axum on three cores: 126k) at the same p99, 1,741 1 MiB reads (axum: 1,370), and 1,126 durable writes from 64 connections (crash-safe axum: 372), in 7.3 MiB against axum's 17-20 MiB. Note 075 has the table.
* Benchmark the HTTP hosts against axumeunhhu2026-09-261-0/+54
| | | | | | | | | | | | A C load generator, an axum service with the same document contract (in memory, fdatasync, and crash-safe replacement), and a runner that pins the servers and the load to separate CPUs. On the Pi 5, Pure uses about 40% less memory, wins with a new connection per request and with eight durable writers (3.2x the crash-safe axum), but loses 5x on keep-alive reads and 1.5x on 64 durable writers: no persistent connections, one thread, eight connection slots and two fsyncs per commit. Note 075 records the numbers and the targets.
* Make the local Pi the verification deviceeunhhu2026-09-251-2/+3
| | | | | | | The recorded Raspberry Pi 5 (Linux AArch64, 16 KiB pages, ext4) replaces Apple Silicon macOS as the device whose results decide completion. The macOS CI job stays as an optional portability check; no macOS support is claimed.
* Let the runtime own working versions as draftseunhhu2026-09-252-5/+102
| | | | | | | | | | | | | | | | | | state.h gives any app a runtime-owned working version of a stored value on the tree store. A draft shares unchanged extents with the stored version, edits in memory by path copying, lends ordered extents without copying, and commits only its new nodes when the key is still at its base revision. A failed commit changes neither the draft nor the store; a draft whose file was replaced by compaction copies its stored extents on commit. Unreachable arena nodes are reclaimed once they outweigh max(reachable, 32 KiB). Typing into the middle of a 1 MiB document and saving each character peaked at about 1,660 KiB RSS with a draft against about 4,480 KiB for an app copy compared with storage on save; saves were only 1-2 ms faster. This corrects 073, which had attributed the TUI's remaining 8 ms to that comparison. Drafts are not yet charged to the runtime budget or visible to .pure definitions.
* Add selected single-file persistent tree storeeunhhu2026-09-251-0/+126
| | | | | | | | | | | | | | | | store-tree.c keeps every document in one append-only file as a persistent B-tree of byte extents, with the key catalog in the same structure. A splice writes only the changed leaf and path; unchanged extents are shared between versions, readers take no lock, and two alternating head slots publish a commit after its nodes are durable. Compaction rewrites reachable nodes. On the recorded ext4 host a durable 1-byte middle insert into a 1 MiB document took 8.58 ms against 78.51 ms for the default store, and the real TUI's Ctrl+S after typing took 16.60 ms against 84.59 ms. check-tree runs the store's crash/oracle tests and the unchanged runtime, splice, async and real-PTY editor checks on it. It stays opt-in: linked code is 12.7 KB larger and contiguous multi-leaf reads copy.
* Verify paged document app under 4 KiB AArch64 kerneleunhhu2026-09-242-0/+33
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* Admit aligned OS pages in selected paged storeeunhhu2026-09-241-0/+36
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* Establish native micro runtime checkpointeunhhu2026-09-2471-0/+6081