PageIndex/tests/test_concurrency.py
mountain 9ad7c687e0 fix: degrade to empty result on LLM retry exhaustion instead of aborting
llm_completion/llm_acompletion raised RuntimeError once retries were
exhausted, which propagated through the unprotected sync TOC-detection
chain (find_toc_pages -> toc_transformer -> toc_extractor -> ...) and
aborted the whole document index — a regression vs. the pre-SDK behavior
that returned "" and let callers degrade (extract_json('') -> {} ->
.get(default), falling back to no-TOC indexing).

Restore the empty-result contract ("" / ("", "error") with
return_finish_reason), now logged at WARNING so the failure is visible
rather than silent. The async gather sites keep return_exceptions=True to
absorb any non-LLM error. A single persistently-failing call no longer
blocks indexing the rest of the document.
2026-07-10 10:49:58 +08:00

478 lines
16 KiB
Python

import asyncio
import threading
import time
from concurrent.futures import ThreadPoolExecutor
from types import SimpleNamespace
import pydantic
import pytest
from pageindex.config import (
IndexConfig,
_env_llm_timeout_default,
_env_max_concurrency_default,
_max_concurrency_scope_semaphore,
get_llm_params,
get_max_concurrency,
llm_params_scope,
max_concurrency_scope,
set_llm_params,
set_max_concurrency,
)
from pageindex.index.utils import (
_llm_semaphore,
_process_ceiling_semaphore,
llm_acompletion,
llm_completion,
)
@pytest.fixture(autouse=True)
def _restore_max_concurrency():
"""Keep tests isolated — the concurrency setting is a module global."""
prev = get_max_concurrency()
yield
set_max_concurrency(prev)
@pytest.fixture(autouse=True)
def _restore_llm_params():
"""Keep tests isolated — llm params are a module global too."""
prev = get_llm_params()
yield
set_llm_params(**prev)
async def _nested_llm_load(state, *, branches=5, leaves=5):
"""Drive branches*leaves leaf calls, nested two levels deep, each holding
the shared per-loop LLM semaphore — the exact shape of the indexing pipeline
(tree_parser gather -> per-node gather -> leaf LLM call)."""
async def leaf():
async with _llm_semaphore():
state["in_flight"] += 1
state["peak"] = max(state["peak"], state["in_flight"])
await asyncio.sleep(0.01)
state["in_flight"] -= 1
async def branch():
await asyncio.gather(*(leaf() for _ in range(leaves)))
await asyncio.gather(*(branch() for _ in range(branches)))
def test_llm_semaphore_bounds_concurrency_even_when_nested():
# The core fix: the cap is a TRUE global bound even when acquired from
# deeply nested gathers. 25 leaf calls nested two levels, cap 3 -> peak 3.
# A per-gather-call semaphore (the previous design) would let this reach
# branches*leaves and blow past the cap.
set_max_concurrency(3)
state = {"in_flight": 0, "peak": 0}
asyncio.run(_nested_llm_load(state, branches=5, leaves=5))
assert state["peak"] == 3
def test_llm_semaphore_is_a_true_process_wide_ceiling_across_threads():
# The bug this fixes: each asyncio.run() (its own event loop) used to get
# an independent full-size semaphore, so N concurrently-indexing threads
# multiplied the effective cap by N. 2 threads, cap=3 -> combined peak
# must stay at 3, not 6.
set_max_concurrency(3)
state = {"in_flight": 0, "peak": 0}
lock = threading.Lock()
async def leaf():
async with _llm_semaphore():
with lock:
state["in_flight"] += 1
state["peak"] = max(state["peak"], state["in_flight"])
await asyncio.sleep(0.05)
with lock:
state["in_flight"] -= 1
async def load():
await asyncio.gather(*(leaf() for _ in range(5)))
threads = [threading.Thread(target=lambda: asyncio.run(load())) for _ in range(2)]
[t.start() for t in threads]
[t.join() for t in threads]
assert state["peak"] == 3
def test_llm_semaphore_cancellation_while_waiting_does_not_leak_a_permit():
# A blocking ceiling_sem.acquire() run via asyncio.to_thread() would leak a
# permit under cancellation: the worker thread can't be interrupted, so if
# the awaiting coroutine is cancelled while the thread is still parked
# inside acquire(), the thread can go on to actually acquire the permit
# *after* the coroutine already unwound, and the matching finally:
# release() never runs for that attempt. Cancel a task waiting on an
# already-exhausted ceiling and confirm the permit count fully recovers.
set_max_concurrency(1)
async def run():
async def hold():
async with _llm_semaphore():
await asyncio.sleep(10)
holder = asyncio.create_task(hold())
await asyncio.sleep(0.1) # let it acquire the single permit
waiter = asyncio.create_task(_llm_semaphore().__aenter__())
await asyncio.sleep(0.1) # let it start waiting for the permit
waiter.cancel()
with pytest.raises(asyncio.CancelledError):
await waiter
holder.cancel()
with pytest.raises(asyncio.CancelledError):
await holder
await asyncio.sleep(0.2) # give any orphaned acquire a chance to land
assert _process_ceiling_semaphore()._value == 1
asyncio.run(run())
def test_scoped_semaphore_cancellation_while_waiting_does_not_over_release():
# Mirror of the ceiling test for the scoped override: a coroutine cancelled
# while polling for a scoped permit must NOT let the finally release a permit
# it never acquired, which would inflate the scoped cap for later calls.
set_max_concurrency(5) # high ceiling so the scope is the narrower cap
async def run():
with max_concurrency_scope(1):
sem = _max_concurrency_scope_semaphore()
assert sem._value == 1
async def hold():
async with _llm_semaphore():
await asyncio.sleep(10)
holder = asyncio.create_task(hold())
await asyncio.sleep(0.1) # holder takes the single scoped permit
waiter = asyncio.create_task(_llm_semaphore().__aenter__())
await asyncio.sleep(0.1) # waiter is now polling for the scoped permit
waiter.cancel()
with pytest.raises(asyncio.CancelledError):
await waiter
holder.cancel()
with pytest.raises(asyncio.CancelledError):
await holder
await asyncio.sleep(0.2)
assert sem._value == 1 # fully recovered, not inflated to 2
asyncio.run(run())
def test_llm_semaphore_uses_scoped_override():
# A per-index max_concurrency_scope active when the loop's semaphore is first
# created must set its size, and must not mutate the process default.
set_max_concurrency(10)
state = {"in_flight": 0, "peak": 0}
async def run():
with max_concurrency_scope(2):
await _nested_llm_load(state, branches=4, leaves=4)
asyncio.run(run())
assert state["peak"] == 2
assert get_max_concurrency() == 10
def test_llm_acompletion_holds_the_shared_semaphore(monkeypatch):
# Prove llm_acompletion actually acquires the shared cap around the async
# network call.
set_max_concurrency(3)
state = {"in_flight": 0, "peak": 0}
async def fake_acompletion(**kwargs):
state["in_flight"] += 1
state["peak"] = max(state["peak"], state["in_flight"])
await asyncio.sleep(0.01)
state["in_flight"] -= 1
return SimpleNamespace(
choices=[SimpleNamespace(message=SimpleNamespace(content="ok"))]
)
monkeypatch.setattr("litellm.acompletion", fake_acompletion)
async def run():
await asyncio.gather(*(llm_acompletion("gpt-x", f"p{i}") for i in range(20)))
asyncio.run(run())
assert state["peak"] == 3
def test_llm_acompletion_passes_a_timeout_to_litellm(monkeypatch):
# A per-request timeout must reach litellm so a hung / half-open connection
# fails fast instead of stalling indexing forever. It rides get_llm_params(),
# so both the default and an override flow through automatically.
seen = {}
async def fake_acompletion(**kwargs):
seen.update(kwargs)
return SimpleNamespace(
choices=[SimpleNamespace(message=SimpleNamespace(content="ok"))]
)
monkeypatch.setattr("litellm.acompletion", fake_acompletion)
asyncio.run(llm_acompletion("gpt-x", "hi"))
assert "timeout" in seen and seen["timeout"] == get_llm_params()["timeout"]
def test_llm_completion_degrades_to_empty_on_exhaustion(monkeypatch, caplog):
# A persistently-failing LLM call must NOT abort the whole index: it returns
# an empty result (logged at WARNING, not silent) so callers degrade
# (extract_json('') -> {} -> .get(default)) and the rest still indexes.
import logging
def boom(**kwargs):
raise RuntimeError("provider down")
monkeypatch.setattr("litellm.completion", boom)
monkeypatch.setattr("pageindex.index.utils.time.sleep", lambda *a: None) # skip retry backoff
with caplog.at_level(logging.WARNING, logger="pageindex.index.utils"):
assert llm_completion("gpt-x", "hi") == ""
assert llm_completion("gpt-x", "hi", return_finish_reason=True) == ("", "error")
assert any("failed after" in r.message and "degrading" in r.message for r in caplog.records)
def test_llm_acompletion_degrades_to_empty_on_exhaustion(monkeypatch):
# Async counterpart: exhausted retries return "" instead of raising, so the
# return_exceptions gathers see a plain empty result and callers degrade.
async def boom(**kwargs):
raise RuntimeError("provider down")
async def _instant_sleep(*a):
return None
monkeypatch.setattr("litellm.acompletion", boom)
monkeypatch.setattr("pageindex.index.utils.asyncio.sleep", _instant_sleep) # skip retry backoff
assert asyncio.run(llm_acompletion("gpt-x", "hi")) == ""
def test_llm_completion_holds_the_shared_semaphore(monkeypatch):
# Sync litellm.completion calls must share the same process-wide cap as the
# async path; otherwise concurrent indexing threads can exceed
# set_max_concurrency().
set_max_concurrency(1)
state = {"in_flight": 0, "peak": 0}
lock = threading.Lock()
def fake_completion(**kwargs):
with lock:
state["in_flight"] += 1
state["peak"] = max(state["peak"], state["in_flight"])
time.sleep(0.02)
with lock:
state["in_flight"] -= 1
return SimpleNamespace(
choices=[
SimpleNamespace(
message=SimpleNamespace(content="ok"),
finish_reason="stop",
)
]
)
monkeypatch.setattr("litellm.completion", fake_completion)
with ThreadPoolExecutor(max_workers=3) as pool:
results = list(pool.map(lambda i: llm_completion("gpt-x", f"p{i}"), range(6)))
assert results == ["ok"] * 6
assert state["peak"] == 1
def test_run_async_propagates_scope_into_worker_thread():
# When build_index runs inside an already-running loop, _run_async hops to a
# worker thread. The max_concurrency_scope override must ride along (copied
# context) and still bound the (nested) LLM load in that worker loop.
from pageindex.index.pipeline import _run_async
set_max_concurrency(10)
state = {"in_flight": 0, "peak": 0}
async def outer():
# We're inside a running loop -> _run_async uses the worker thread.
with max_concurrency_scope(3):
_run_async(_nested_llm_load(state, branches=4, leaves=4))
asyncio.run(outer())
assert state["peak"] == 3
def test_set_get_max_concurrency_round_trip():
set_max_concurrency(3)
assert get_max_concurrency() == 3
def test_set_max_concurrency_rejects_invalid():
# bool is an int subclass -> must be rejected, not silently -> Semaphore(1).
for bad in (0, -1, True, False, 2.5, "3", None):
with pytest.raises(ValueError):
set_max_concurrency(bad)
def test_env_default_parsing(monkeypatch):
monkeypatch.delenv("PAGEINDEX_MAX_CONCURRENCY", raising=False)
assert _env_max_concurrency_default() == 5
monkeypatch.setenv("PAGEINDEX_MAX_CONCURRENCY", "20")
assert _env_max_concurrency_default() == 20
monkeypatch.setenv("PAGEINDEX_MAX_CONCURRENCY", "garbage")
assert _env_max_concurrency_default() == 5
monkeypatch.setenv("PAGEINDEX_MAX_CONCURRENCY", "0")
assert _env_max_concurrency_default() == 5
def test_env_llm_timeout_parsing(monkeypatch):
monkeypatch.delenv("PAGEINDEX_LLM_TIMEOUT", raising=False)
assert _env_llm_timeout_default() == 120
monkeypatch.setenv("PAGEINDEX_LLM_TIMEOUT", "45")
assert _env_llm_timeout_default() == 45
monkeypatch.setenv("PAGEINDEX_LLM_TIMEOUT", "garbage")
assert _env_llm_timeout_default() == 120
monkeypatch.setenv("PAGEINDEX_LLM_TIMEOUT", "0") # <=0 opts out of the timeout
assert _env_llm_timeout_default() is None
def test_index_config_max_concurrency_field():
# Default is None → "use the global/env default"; explicit value overrides.
assert IndexConfig().max_concurrency is None
assert IndexConfig(max_concurrency=7).max_concurrency == 7
def test_index_config_rejects_bool_and_non_positive_max_concurrency():
# bool would otherwise be coerced by pydantic to 1/0; both must be rejected.
for bad in (True, False, 0, -1):
with pytest.raises(pydantic.ValidationError):
IndexConfig(max_concurrency=bad)
def test_max_concurrency_scope_overrides_then_restores():
# A per-index override applies inside the scope and, crucially, does NOT
# stick as the new process default afterwards (no stickiness).
set_max_concurrency(10)
with max_concurrency_scope(3):
assert get_max_concurrency() == 3
assert get_max_concurrency() == 10
def test_max_concurrency_scope_none_is_a_no_op():
set_max_concurrency(8)
with max_concurrency_scope(None):
assert get_max_concurrency() == 8
assert get_max_concurrency() == 8
def test_max_concurrency_scope_rejects_invalid():
for bad in (0, -1, True, False):
with pytest.raises(ValueError):
with max_concurrency_scope(bad):
pass
def test_max_concurrency_scope_is_isolated_across_threads():
# A per-index override in one indexing thread must not leak into another
# thread indexing a different document concurrently. The override is a
# ContextVar, so it's invisible outside its own context.
set_max_concurrency(10)
seen = {}
barrier = threading.Barrier(2)
def worker():
with max_concurrency_scope(2):
barrier.wait() # let main read while we're inside the scope
seen["worker"] = get_max_concurrency()
barrier.wait()
t = threading.Thread(target=worker)
t.start()
barrier.wait()
seen["main"] = get_max_concurrency()
barrier.wait()
t.join()
assert seen["worker"] == 2 # worker sees its own scoped override
assert seen["main"] == 10 # main is unaffected by the worker's scope
def test_llm_params_scope_overrides_then_restores():
set_llm_params(temperature=0)
with llm_params_scope({"temperature": 1}):
assert get_llm_params()["temperature"] == 1
assert get_llm_params()["temperature"] == 0
def test_llm_params_scope_none_is_a_no_op():
set_llm_params(temperature=0)
with llm_params_scope(None):
assert get_llm_params()["temperature"] == 0
assert get_llm_params()["temperature"] == 0
def test_llm_params_scope_rejects_reserved_keys():
with pytest.raises(ValueError):
with llm_params_scope({"model": "x"}):
pass
def test_llm_params_scope_is_isolated_across_threads():
set_llm_params(temperature=0)
seen = {}
barrier = threading.Barrier(2)
def worker():
with llm_params_scope({"temperature": 1}):
barrier.wait()
seen["worker"] = get_llm_params()["temperature"]
barrier.wait()
t = threading.Thread(target=worker)
t.start()
barrier.wait()
seen["main"] = get_llm_params()["temperature"]
barrier.wait()
t.join()
assert seen["worker"] == 1
assert seen["main"] == 0
def test_llm_params_scope_does_not_leak_across_concurrent_indexing():
# The bug this fixes: set_llm_params() mutates a bare process-wide dict, so
# two documents indexed concurrently with different llm_params_scope()
# overrides must not see each other's temperature.
set_llm_params(temperature=0)
seen = {"a": None, "b": None}
async def job(name, temperature, delay_before, delay_after):
with llm_params_scope({"temperature": temperature}):
await asyncio.sleep(delay_before)
seen[name] = get_llm_params()["temperature"]
await asyncio.sleep(delay_after)
async def run():
await asyncio.gather(
job("a", 1, 0.0, 0.05),
job("b", 2, 0.02, 0.0),
)
asyncio.run(run())
assert seen["a"] == 1
assert seen["b"] == 2
def test_utils_star_import_does_not_leak_config_name():
# `from .utils import *` (used by the page_index modules) must not export a
# name `config` that would shadow the real pageindex.config submodule for
# those modules. The SimpleNamespace alias is now `_config`.
ns = {}
exec("from pageindex.index.utils import *", ns)
assert "config" not in ns