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* 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