- concurrency.loop_semaphore: per-event-loop semaphores (safe across pytest loops
and process restarts via a WeakKeyDictionary keyed by the running loop).
- provider: holds a per-account (≤4) and per-host (PER_HOST_CONN_CAP) slot for the
whole lifetime of an IMAP socket, released on close; SMTP send takes a per-host
slot for its duration. A worker can no longer open hundreds of sockets to one
host/account.
- indexer: parsing goes through a PARSE_CONCURRENCY semaphore, and a message over
STREAM_PARSE_MB is parsed from its blob file (parse_message_file) instead of an
in-memory tree, so peak RAM ~= PARSE_CONCURRENCY x STREAM_PARSE_MB regardless of
mailbox sizes. Backfill parallelism stays bounded by the bulk queue only.
- config: PER_HOST_CONN_CAP, PARSE_CONCURRENCY, STREAM_PARSE_MB.
- tests: per-account cap blocks the 5th connection / distinct accounts independent;
file-vs-bytes parse equivalence + large-message streaming routing.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Each owned account is tiered by the coordinator; the runner shapes its work to
match — correctness identical, only latency/socket cost differ.
- hot: persistent INBOX IDLE + secondary poll every POLL_WARM.
- warm: no persistent socket; transient INBOX+special poll every POLL_WARM.
- cold: same transient poll every POLL_COLD.
- engine: poll_all_loop (transient full poll); secondary_poll_loop interval is
now a parameter; POLL_INTERVAL removed in favor of POLL_WARM/POLL_COLD.
- coordinator: tier eval every 120s from session heat (sess:active:{user}) +
recent mail (max internal_date within TIER_HOT_ACTIVITY_H), with the
HOT_BUDGET_PER_WORKER guard shedding least-recently-active session-less hot
accounts; user.active event promotes a user's accounts to hot at once (≤5s).
- API: login + WS connect/ping publish user.active and refresh sess:active
(TTL TIER_SESSION_GRACE_MIN). New sync:tier:{id} key, default warm on claim.
- config: POLL_WARM/POLL_COLD/TIER_*/HOT_BUDGET_PER_WORKER.
- tests: 5 tier tests (session/recent-mail promotion, cold, user.active,
budget demotion) alongside the lease/lifecycle acceptance tests.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Ownership of an account now moves through a Redis lease so any number of sync
workers can run against the same account set with no double-IDLE.
- leases.py: sync:live registry + sync:lease:{id} (SET NX EX) with owner-checked
Lua renew/release; mark_live / mark_not_live helpers.
- coordinator.py: SyncCoordinator claims from sync:live up to MAX_ACCOUNTS_PER_
WORKER, renews every LEASE_RENEW (fences the runner on lease loss), reconciles
sync:live against Postgres, heartbeats a worker key, and rebalances when it
holds well above a fair share.
- supervisor start/stop now drive a coordinator; engine._set_state and
delete_account maintain sync:live membership (+ lease drop = fencing teardown).
- config: MAX_ACCOUNTS_PER_WORKER, LEASE_TTL, LEASE_RENEW.
- tests: acceptance 1-3 (single ownership, crash failover, create/delete
lifecycle) driving the real coordinator + Redis with faked IMAP loops.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
lukasandClaude Opus 4.8