[antosubash]

Performance fix for tenant membership lookups and the members page (local performance review, 2026-11-05).

• Single-flight cache fills. simple_module_core.singleflight adds SingleFlight, a per-key lock that is dropped when idle, and fill().
  • fill() is an epoch-checked fill. It caches nothing if an invalidation lands during the read. After MAX_FILL_ATTEMPTS (3) it returns the last read uncached, so a request cannot loop.
  • Three caches use it: the tenants memberships cache, the permissions direct-grants cache and the tenant subdomain lookup.
  • Concurrent misses for one user go from N database reads to 1. Measured with 50 concurrent requests:
    • memberships: 50 → 1
    • grants: 50 → 1
    • repeated unknown slug: 50 → 1
• Unknown subdomains are cached as missing for 5 s.
  • Host invalidations get their own channel, tenants.hosts, keyed by slug or None. tenants.membership carries only user ids.
  • Tenant creation drops only the owner's memberships and the new slug, after commit, on every worker. Before, the review draft cleared every user's cache on each self-service creation.
  • Status changes and deletion still clear everything.
• Member list pagination uses the repo's Page/paginate/PaginationBar, ordered by (created_at, id), 25 per page (max 200). The page keeps its current page after a mutation, and the members count is computed once per load.
• Breaking:
  • GET current-members now returns {items, total, page, per_page, pages} instead of an array.
  • TenantService.list_members(tenant_id, params) takes PageParams and returns Page[Membership].
  • TenantService takes invalidate_hosts=; deps.get_tenant_service wires it.
  • All of this is in CHANGELOG and docs/modules/tenants.md.
• The users session-version cache can adopt fill() in a follow-up. Its files are changed by fix(users): CSRF-protect browser auth requests; logout retires the browser session #832.

Pipeline:

• /optimize ran once.
• An automated security check raised two findings, both fixed before review: tenant creation flushed every user's cache, and the fill retries were unbounded.
• Two review rounds. Pass 1 led to: the separate hosts channel, so a non-UUID subject id such as host:… can no longer be misrouted; one shared fill() helper in place of three copies; a single member count; and the api_tokens test that read the old array.

Local CI: make lint ✓ · make test-py (8 workers) 7890 passed ✓ · make test-js ✓.

https://claude.ai/code/session_01M9neheZZEe3sVpDi2S3zT4

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
🔒 Security Review	✅ Completed 2026-11-05T17:35:10.405406Z	88fd939	PR opened

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