Review of the capacity work surfaced three real defects and two gaps:
- A peer dribbling bytes re-armed the 10s handshake read timeout on
every read and held its accept permit forever; 128 such sockets
wedged the accept loop for good. The handshake now has one deadline
across all reads, plus a 4 KiB cap on buffered handshake bytes.
- A capacity refusal was logged and swallowed, leaving the refused
peer's queued downloads stuck until the caller's own timeout. Both
registration paths now fail those downloads so the caller gets a
verdict, and the listener only announces PeerConnected when the
registration actually happened.
- The transfer-claim was undone by the worker thread writing Queued
back over it; that write is gone, so a replayed TransferResponse
can no longer start a second writer on the same .part file.
- Offered uploads and queue waiters joined the eviction-protected
set, and the browse protection window matches the minutes a real
share listing takes rather than one.
Regression tests: the broker-timeout sweep failing a queued download
end to end, the replay guard observed over a real socket, and the
handshake deadline against a dribbling and an oversized peer.
One popular search produced a ConnectToPeer for every responder, and
each one cost a 2 MiB wrapper thread, an unbounded 256 KiB actor, a
listener thread per inbound socket, and on failure a 2 MiB thread that
slept for 20 seconds. A container with a pids limit died on one album
search (issues #32, #33).
Four bounds, no behavior change for a quiet session:
- P-type registrations run inline on the ops loop; only F transfers
keep a worker thread. The dial already ran on the actor thread.
- The broker timeout is a deadline swept by the ops loop instead of a
sleeping thread per failed dial.
- The registry caps live actors (default 512, Client::set_max_peers).
At capacity the oldest peer outside the caller's protected set
(live downloads, uploads, pending serves, queued messages, browses
in flight) is evicted; if none qualify the registration is refused
before any thread is spawned.
- Concurrent listener handshakes are bounded by a 128-permit
semaphore released once the peer-init arrives, so slow handshakes
cannot multiply threads while transfers stay unthrottled.
A replayed TransferResponse for an InProgress or Completed token is
dropped instead of starting a second transfer thread over the same
.part file.
Fixes#32Fixes#33
The peer listener died with "Too many open files (os error 24)" on any
long-lived non-daemon session: only the daemon raised RLIMIT_NOFILE, and
peer sockets were unbounded — no idle reaping, no deadlines on accepted
transfer streams, and one peer could hold two connections under split
registry identities.
- raise the open-file limit at the top of run(), for every entry point,
and warn from Client::connect when the soft limit is below 1024
- reap peer control connections idle for five minutes; a clean
disconnect no longer discards the peer's queued uploads
- give listener-supplied download streams and upload serving the same
read/write deadlines dialled sockets already had
- register inbound peers under their plain username so the registry
holds one connection per peer, and announce them like pierced ones
- hold the registry lock across actor spawn + insert and surface
thread-spawn failure, so an instantly-dead peer cannot leave a
zombie entry
Seven region audits, every finding adversarially verified against the
whole workspace before being applied; 80 landed and the two that failed
in application were refuted honestly (ParseError has a from_str_radix
producer the audit missed; NatPmpError's Display is the only reader of
its diagnostic payloads).
The bigger cuts:
- The NewPeer/PierceFireWall cluster: an operation variant nothing ever
sent, its 77-line arm, a protocol-wrong Client::pierce_firewall that
wrote a peer-init frame down the server socket, and the struct only
they used. The live paths in peer/listen.rs are untouched.
- The ops loop reads `for operation in reader` instead of hand-rolling
recv/break, de-indenting the whole dispatch body.
- Dead lib surface: Message::print_hex and four unused accessors,
UploadFailed, registry and actor getters, build_watch_user,
strip_ansi_codes, delegating shims on ClientContext. Removing public
items makes this a semver major, which the release pipeline enforces.
- Never-used flexibility: the state-migration framework that never held
a migration, border-type helpers that all answered Rounded, the TUI's
max_concurrent_downloads field nothing read.
- Convergence: six poll loops into poll_until, three wrap-around
navigation blocks into cycle, hit tests into Rect::contains, char
walkers into floor/ceil_char_boundary, five Download literals into
one helper, the suites' shared scaffolding into tests/common.
Deliberately not taken: swapping the hand-rolled zlib inflate and MD5
for crates (they replace wire-facing machinery whose tolerance of
real-world peer quirks no local test exercises) and pulling chrono into
the lib for a log timestamp. Recorded for their own decision.
Net -1002 lines. Both e2e modes stay green: 94 CLI tests each way, 16
protocol, 33 lib, unit suites, clippy pedantic clean, aislop 100/100
with the four scanner false positives suppressed inline where they
fire.
client/mod.rs had grown to 1124 lines, a third of it tests: six loose #[test]
functions wedged between the two `impl ClientContext` blocks, plus the usual
`mod tests` at the bottom. Both now live in client/tests.rs, leaving mod.rs at
790 lines of actual client.
Same 11 tests, same 568 passing across the workspace.
Michel de Graaf