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4250713700
* fix(spend_counter): seed Redis counter via SET NX to prevent cross-pod double-seed
Symptom
-------
Customers on multi-pod deployments see team `spend` jump to ~2x (or N x
the pod count) shortly after a Redis cache miss / TTL expiry, triggering
spurious "Budget Crossed" alerts and blocked requests until the value is
manually reset.
Root cause
----------
`SpendCounterReseed.coalesced` warmed the primary spend counter by
calling `redis.async_increment(key, value=db_spend, refresh_ttl=True)`,
which lowers to Redis `INCRBYFLOAT`. That is additive, not idempotent.
The per-counter `asyncio.Lock` only coalesces seeders inside one
process. With N pods sharing one Redis, on a cold key (cold start, TTL
expiry, manual delete) every pod independently passes its lock + Redis
re-check, reads the same `db_spend`, and issues `INCRBYFLOAT db_spend`.
Final value: N x db_spend.
Fix
---
Use `redis.async_set_cache(key, value=db_spend, nx=True)` for the seed.
SET NX is atomic across pods: exactly one writer initializes the key;
losers read the winner's value via `async_get_cache`. This is the same
idiom already used by `coalesced_window` in the same file, so the two
seed paths are now consistent.
Per-request deltas continue to use `INCRBYFLOAT` (correct - additive
behaviour is what we want for increments, not for initial seed).
Verification
------------
Live two-process repro against the same Postgres + Redis (DB
spend = 506):
Unpatched: 4/4 runs -> Redis counter = ~1012 (~2 x db_spend)
Patched: 12/12 runs -> Redis counter = ~506
Unit tests (`test_proxy_server.py`):
- New `test_primary_spend_counter_redis_concurrent_seed_does_not_double_seed`
patches `_get_lock` to return a fresh lock per caller (otherwise the
per-process lock masks the race), races two `coalesced` calls, and
asserts final = 506 with exactly one of two SET NX attempts winning.
- 4 existing tests updated for the new seed contract (SET NX for the
seed, INCRBYFLOAT only for the per-request delta).
- Full `spend_counter or reseed or budget` slice: 22 passed.
Co-authored-by: Cursor <cursoragent@cursor.com>
* test(spend_counter): make SET NX mock atomic so loser branch is exercised
Greptile flagged that `redis_set_cache` in
test_primary_spend_counter_redis_concurrent_seed_does_not_double_seed
placed `await asyncio.sleep(0)` AFTER the NX membership check. Both
concurrent tasks observed an empty `redis_store`, passed the guard, and
both returned True - so the loser branch (else: read back winner's value)
was never exercised.
Fix the mock to model real atomic Redis SET NX:
- Yield BEFORE the membership check so two concurrent callers interleave
the way real SET NX does (first to resume runs check + write atomically
and wins; second resumes after the key exists and loses).
- Track set_cache return values; assert sorted([loser, winner]) so we
know exactly one task wins and one loses.
- Track async_get_cache calls that happen AFTER at least one SET NX has
completed; assert at least one such read - that is the loser-path
fallback (`current_value = float(cached)` when seeded is False).
Verified by temporarily reverting the mock to the old order: the test
now fails with `expected exactly one SET NX winner and one loser, got
[True, True]`, exactly the failure mode Greptile described.
No production code change.
Co-authored-by: Cursor <cursoragent@cursor.com>
* test(spend_counter): mock async_set_cache to populate redis_store in concurrent read+write test
`test_concurrent_read_and_write_paths_share_one_db_query` mocks
`async_increment` to populate the in-memory `redis_store`, but did not
mock `async_set_cache`. After the SET-NX seed change in `coalesced()`,
the seed step writes via `async_set_cache(nx=True)` (default AsyncMock,
no `redis_store` write), so the simulated Redis stays empty after the
first reseed. The second `get_current_spend` then sees a clean Redis
miss, re-enters the DB read path, and the test fails with
`expected 1 DB query, got 2`.
Fix: add a `redis_set_cache` side_effect that updates `redis_store` on
`nx=True` (and rejects when the key already exists), matching the
pattern used by the four sibling tests fixed in this branch's first
commit. Pre-existing assertions are unchanged.
Full `tests/test_litellm/proxy/test_proxy_server.py`: 158 passed.
Co-authored-by: Cursor <cursoragent@cursor.com>
---------
Co-authored-by: Cursor <cursoragent@cursor.com>
(cherry picked from commit
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|---|---|---|
| .. | ||
| _experimental/mcp_server | ||
| agent_endpoints | ||
| anthropic_endpoints | ||
| auth | ||
| client | ||
| common_utils | ||
| db | ||
| discovery_endpoints | ||
| experimental/mcp_server | ||
| google_endpoints | ||
| guardrails | ||
| health_endpoints | ||
| hooks | ||
| image_endpoints | ||
| management_endpoints | ||
| management_helpers | ||
| memory | ||
| middleware | ||
| openai_files_endpoint | ||
| pass_through_endpoints | ||
| policy_engine | ||
| prompts | ||
| public_endpoints | ||
| rag_endpoints | ||
| realtime_endpoints | ||
| response_api_endpoints | ||
| spend_tracking | ||
| test_configs | ||
| types_utils | ||
| ui_crud_endpoints | ||
| vector_store_endpoints | ||
| __init__.py | ||
| conftest.py | ||
| test_aiohttp_cleanup_closed.py | ||
| test_aiohttp_session_recovery.py | ||
| test_api_key_masking_in_errors.py | ||
| test_audio_speech_prometheus_hooks.py | ||
| test_batch_expiry.py | ||
| test_batch_metadata_none_fix.py | ||
| test_batch_retrieve_bedrock.py | ||
| test_budget_reservation.py | ||
| test_caching_routes.py | ||
| test_chat_completion_metadata.py | ||
| test_common_request_processing.py | ||
| test_cors_config.py | ||
| test_custom_proxy.py | ||
| test_empty_model_list.py | ||
| test_enforce_user_param.py | ||
| test_fallback_management_endpoints.py | ||
| test_fastapi_offline_routes.py | ||
| test_filter_models_by_team_access_group.py | ||
| test_health_check_functions.py | ||
| test_health_check_max_tokens.py | ||
| test_langfuse_passthrough_security.py | ||
| test_lazy_openapi_snapshot.py | ||
| test_litellm_pre_call_utils.py | ||
| test_max_budget_env_var.py | ||
| test_model_dump_with_preserved_fields.py | ||
| test_model_id_header_propagation.py | ||
| test_model_info_default_limits.py | ||
| test_model_level_guardrails.py | ||
| test_openapi_schema_validation.py | ||
| test_pricing_field_strip.py | ||
| test_prometheus_cleanup.py | ||
| test_provider_url_destination_guard.py | ||
| test_proxy_cli.py | ||
| test_proxy_server.py | ||
| test_proxy_types.py | ||
| test_proxy_utils.py | ||
| test_pyroscope.py | ||
| test_redis_auth_cache_flag.py | ||
| test_response_model_sanitization.py | ||
| test_route_a2a_models.py | ||
| test_route_llm_request.py | ||
| test_sensitive_route_auth.py | ||
| test_shared_health_check.py | ||
| test_spend_log_cleanup.py | ||
| test_swagger_chat_completions.py | ||
| test_team_member_update.py | ||
| test_team_org_move.py | ||
| test_tools_allowlist_enforcement.py | ||
| test_update_llm_router_resilience.py | ||
| test_utils.py | ||