A picture group's batch has 30-55k release keys; an advisory lock each
ran Postgres out of shared memory (max_locks_per_transaction), and those
batches failed with HTTP 500 (the ranges went back, nothing stored).
A chunk only matches releases of its range's group, so one lock per
group serializes exactly the writers that could both start an upload.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A poster re-uploading under the same name made one release of all
uploads: in a sample, 24% of releases with 2+ files had a file name more
than once (4.3% of files extra copies), 70% of those copies posted a day
or more apart; their NZBs listed each copy.
- File assembly keeps a re-upload's copy apart: a part already in every
open copy, posted more than 3 h from them, starts another copy; a
missing part fills the nearest copy (a re-send of what was missing),
a re-sent part near a copy that has it is ignored as before.
- A key's files in a batch split into uploads where posting pauses for
more than 3 h, counted from the latest article posted so far (a file
that takes hours to post doesn't split it); each upload is judged and
chunked on its own (ReleaseChunk.upload, .postedLast; candidates carry
their upload).
- The catalog matches a chunk to the release of its key whose articles
the range's group owns and whose posting window is within 3 h, else
starts one (key, key:2, …): releases get identity_key, group_id,
last_posted_at. Keys are locked in order (advisory locks), so
concurrent batches neither deadlock nor both start one; the merger
writes in key order too. The same upload multi-posted to other groups
is a release per group.
- The gap: 91% of uploads post within 3 h; 73% of re-uploaded copies
come later (releases:upload-gaps). releases:duplicates measures the
duplicate names.
Both implementations; check.ts compares the windows and uploads too
(identical on all captures; Rust tests mirror the TypeScript cases).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The merger's neighbour query matched "end_id = ? OR start_id = ?", which
no index serves: it read every range of the group per file, 5.5 s a
round and most of Postgres's time in an end-to-end run. Now the range
holding the article before and after, by (group_id, start_id): 0.08 ms.
The prefetcher's leased and started ranges (every 2 s) get partial
indexes: 15-25 ms -> <0.1 ms with 145k planned ranges.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Waiting files counted as work, so the merge loop re-read them for its
whole 30 s budget every minute: Postgres used ~a core even without
workers. Now ~4% at rest, and storing a boneless range costs Postgres
~0.7–1.9 s of CPU (it was 33 s with the loop running). Chunk payloads
are stored EXTERNAL (zstd already; no pglz attempt).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The neighbour check was three queries per file (~2,000 files/minute); now
one per round of 20k files, with a cursor so waiting files don't take
every round's places, and rounds until nothing is left or 30 s. On the
dev backlog (old-style fragments): ~18k files/minute in the 30 s budget;
at full throughput the new fragment rule leaves ~1,200 files/minute.
A group that fails GROUP (gone from the server) no longer stops planning
the others; edge:bench's groups are inactive.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Files cut by a range's edge are put together once the ranges around them
are done (coordinator:run, every minute): a complete file is judged by the
rules and written as a release chunk with probe candidates; one still
missing parts while both neighbouring ranges are done is dropped and
counted (incomplete/edge). A neighbour not planned yet counts as not done,
except before the group's oldest article. BatchStore.writeReleases is the
shared write path.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
