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* 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
|
||
|---|---|---|
| .. | ||
| a2a_protocol | ||
| anthropic_interface/exceptions | ||
| caching | ||
| completion_extras | ||
| containers | ||
| enterprise | ||
| expected_fine_tuning_api | ||
| expected_responses_api_request | ||
| experimental_mcp_client | ||
| google_genai | ||
| images | ||
| integrations | ||
| interactions | ||
| litellm_core_utils | ||
| llms | ||
| ocr | ||
| passthrough | ||
| proxy | ||
| responses | ||
| router_strategy | ||
| router_utils | ||
| secret_managers | ||
| test_router | ||
| types | ||
| vector_stores | ||
| __init__.py | ||
| conftest.py | ||
| log.txt | ||
| readme.md | ||
| test_a2a_registry_lookup.py | ||
| test_acompletion_session_reuse_e2e.py | ||
| test_add_deployment_no_master_key.py | ||
| test_aembedding_session_reuse_e2e.py | ||
| test_anthropic_beta_headers_filtering.py | ||
| test_anthropic_skills_transformation.py | ||
| test_azure_video_router.py | ||
| test_bedrock_anthropic_1hr_cache_pricing.py | ||
| test_chat_ui_responses_session.py | ||
| test_claude_haiku_4_5_config.py | ||
| test_claude_opus_4_6_config.py | ||
| test_completion_timeout_resolution.py | ||
| test_compression.py | ||
| test_constants.py | ||
| test_container_router.py | ||
| test_cost_calculation_log_level.py | ||
| test_cost_calculator.py | ||
| test_count_tokens_public_api.py | ||
| test_dashscope_image_generation.py | ||
| test_deepseek_model_metadata.py | ||
| test_dockerfile_non_root.py | ||
| test_eager_tiktoken_load.py | ||
| test_exception_exports.py | ||
| test_exception_header_preservation.py | ||
| test_exception_mapping_request_attribute.py | ||
| test_filter_out_litellm_params.py | ||
| test_get_blog_posts.py | ||
| test_gpt_image_cost_calculator.py | ||
| test_groq_streaming_encoding.py | ||
| test_lazy_imports.py | ||
| test_litellm_params_reserved_keys.py | ||
| test_logging.py | ||
| test_lowest_latency_zero_tokens.py | ||
| test_main.py | ||
| test_main_module_header.py | ||
| test_model_cost_aliases.py | ||
| test_model_param_helper.py | ||
| test_model_response_normalization.py | ||
| test_nested_drop_params.py | ||
| test_openai_embedding_encoding_format_default.py | ||
| test_project_alias_tracking.py | ||
| test_project_tags_pydantic.py | ||
| test_redact_string_in_error_paths.py | ||
| test_redis.py | ||
| test_register_model_custom_pricing.py | ||
| test_responses_api_bridge_non_stream.py | ||
| test_responses_id_security.py | ||
| test_retrieve_batch_bedrock_dispatch.py | ||
| test_router.py | ||
| test_router_google_genai.py | ||
| test_router_model_cost_isolation.py | ||
| test_router_order_fallback.py | ||
| test_router_per_deployment_num_retries.py | ||
| test_router_redis_init.py | ||
| test_router_retry_non_retryable_errors.py | ||
| test_router_silent_experiment.py | ||
| test_secret_redaction.py | ||
| test_service_logger.py | ||
| test_setup_wizard.py | ||
| test_shared_session_integration.py | ||
| test_ssl_verify_unit.py | ||
| test_stream_chunk_builder_annotations.py | ||
| test_streaming_connection_cleanup.py | ||
| test_system_message_format_bug.py | ||
| test_utils.py | ||
| test_utils_module_docstring.py | ||
| test_uuid_helper.py | ||
| test_vcr_safe_body_matcher.py | ||
| test_video_generation.py | ||
| test_xai_grok_4_3_model_metadata.py | ||
| test_xai_responses_auto_routing.py | ||
Testing for litellm/
This directory 1:1 maps the the litellm/ directory, and can only contain mocked tests.
The point of this is to:
- Increase test coverage of
litellm/ - Make it easy for contributors to add tests for the
litellm/package and easily run tests without needing LLM API keys.
File name conventions
litellm/proxy/test_caching_routes.pymaps tolitellm/proxy/caching_routes.pytest_<filename>.pymaps tolitellm/<filename>.py