hermes-agent/tests/agent/test_idle_compaction_lock_and_guards.py
Teknium ec5835ab8b
fix(compression): persist anti-thrash state across process restarts (#69872)
The anti-thrash guard (_ineffective_compression_count) was in-memory
only: a fresh compressor bound to a resumed, already-compacted session
started with compression_count=0 and a disarmed guard, so a
near-threshold session could legally re-compact once per process
restart, forever.

Persist the counter through the durable session-state channel,
mirroring the failure-cooldown (#54465) and fallback-streak (af7dceaf7)
pattern:

- hermes_state.py: sessions.compression_ineffective_count column
  (declarative reconciliation adds it on existing DBs) +
  get/set_compression_ineffective_count accessors.
- context_compressor.py: every strike/clear verdict routes through
  _record_ineffective_compression_verdict() which writes through to the
  session row (no-change verdicts skip the DB write);
  bind_session_state() loads the persisted value; the compression
  rotation boundary carries the counter onto the child row;
  update_model()'s reset also clears the durable copy; the
  ineffective-only fast path in _automatic_compression_blocked() is
  removed because the counter is now durable and another agent's clear
  must unblock a stale local snapshot.
- conversation_compression.py: _refresh_persisted_compression_guards
  re-reads the counter alongside cooldown + fallback streak.

Reset semantics are unchanged: any real provider reading below the
threshold still clears the counter — and now clears it durably too.

Resolves the residual gap identified in #54923 by @lanyusea (the
second-threshold mechanism was superseded by persisting the existing
guard state).

Co-authored-by: lanyusea <lanyusea@gmail.com>
2026-07-23 08:08:48 -07:00

291 lines
12 KiB
Python

"""Idle-triggered compaction: interaction with the compression guards.
The idle trigger (``agent/turn_context.py``, opt-in via
``compression.idle_compact_after_seconds``) does not compress anything
itself — it routes through ``agent._compress_context`` (the forwarder to
``agent.conversation_compression.compress_context``), which owns ALL of the
automatic-compaction guards:
- the per-session compression lock (added after the idle-compaction PR was
written — an idle-triggered compress racing a turn-triggered one on the
same session_id must be serialized, not forked),
- the persisted summary-failure cooldown,
- the anti-thrash / fallback-streak breaker.
These tests pin that composition end-to-end with a real ``AIAgent`` wired to
a real ``SessionDB``: when a guard says no, the idle path must be a strict
no-op for the turn (no compressor call, no session rotation, no flush
re-baseline, no user-message re-anchor).
"""
from __future__ import annotations
import time
import types
from pathlib import Path
from unittest.mock import MagicMock, patch
from hermes_state import SessionDB
from agent.turn_context import build_turn_context
from tests.agent.test_compression_concurrent_fork import _build_agent_with_db
def _prep_idle_agent(db: SessionDB, session_id: str, *, idle_after: int = 60,
idle_gap: float = 3600.0):
"""Real AIAgent (mock compressor) primed so the idle trigger is eligible."""
agent = _build_agent_with_db(db, session_id)
agent.compression_enabled = True
agent.compression_idle_compact_after_seconds = idle_after
agent._last_activity_ts = time.time() - idle_gap
# The idle block reads these from the compressor; give the MagicMock real
# numbers so the floor computation and the preflight gate behave.
agent.context_compressor.threshold_tokens = 100_000
agent.context_compressor.summary_target_ratio = 0.20
agent.context_compressor.protect_first_n = 2
agent.context_compressor.protect_last_n = 2
# No active failure cooldown unless a test installs one.
agent.context_compressor.get_active_compression_failure_cooldown = (
lambda *a, **k: None
)
agent._cached_system_prompt = "SYSTEM"
return agent
def _run_prologue(agent, history, user_message="hello again"):
"""Invoke ``build_turn_context`` the way ``conversation_loop`` does.
The token-threshold preflight gate is pinned False so these tests
exercise the IDLE trigger in isolation (the preflight path has its own
coverage in ``test_turn_context.py``).
"""
with patch("agent.auxiliary_client.set_runtime_main", lambda *a, **k: None), \
patch("agent.turn_context._should_run_preflight_estimate",
return_value=False), \
patch("agent.turn_context.estimate_request_tokens_rough",
return_value=999_999):
return build_turn_context(
agent=agent,
user_message=user_message,
system_message=None,
conversation_history=history,
task_id=None,
stream_callback=None,
persist_user_message=None,
restore_or_build_system_prompt=lambda *a, **k: None,
install_safe_stdio=lambda: None,
sanitize_surrogates=lambda s: s,
summarize_user_message_for_log=lambda s: str(s),
set_session_context=lambda _sid: None,
set_current_write_origin=lambda _o: None,
ra=lambda: types.SimpleNamespace(_set_interrupt=lambda *a, **k: None),
)
def _history(n: int = 20) -> list:
return [{"role": "user", "content": f"m{i}"} for i in range(n)]
def test_idle_compaction_runs_through_guarded_path_and_releases_lock(
tmp_path: Path,
) -> None:
"""Happy path: the idle trigger reaches the real ``compress_context``.
It must acquire + release the per-session lock, invoke the compressor
exactly once, and (rotation mode) rotate the session — proving the trigger
is wired through the guarded entrypoint rather than calling the compressor
directly.
"""
db = SessionDB(db_path=tmp_path / "state.db")
sid = "IDLE_HAPPY"
db.create_session(sid, source="cli")
agent = _prep_idle_agent(db, sid)
ctx = _run_prologue(agent, _history())
agent.context_compressor.compress.assert_called_once()
# Rotation mode (in_place=False in the shared fixture) creates a child.
assert agent.session_id != sid
# The lock keyed on the OLD session id must not leak.
assert db.get_compression_lock_holder(sid) is None
# The turn continues on the compacted transcript, with the user-message
# anchor pointing at a live user row in the rebuilt list.
assert 0 <= ctx.current_turn_user_idx < len(ctx.messages)
assert ctx.messages[ctx.current_turn_user_idx].get("role") == "user"
def test_idle_compaction_status_suppressed_when_engine_opts_out(
tmp_path: Path,
) -> None:
"""Quiet context engines silence the 💤 idle-resume status line too.
The idle emit routes through ``automatic_compaction_status_message``
(phase="idle") the same way the preflight and pre-API emits do — an
engine with ``emit_automatic_compaction_status = False`` gets a fully
silent idle compaction, while the compaction itself still runs.
"""
db = SessionDB(db_path=tmp_path / "state.db")
sid = "IDLE_QUIET"
db.create_session(sid, source="cli")
agent = _prep_idle_agent(db, sid)
agent.context_compressor.emit_automatic_compaction_status = False
events = []
agent.status_callback = lambda ev, msg: events.append((ev, msg))
_run_prologue(agent, _history())
agent.context_compressor.compress.assert_called_once()
assert not any(
"Resumed after" in str(msg) for _ev, msg in events
), f"idle status leaked despite quiet engine: {events}"
def test_idle_compaction_status_emitted_by_default(tmp_path: Path) -> None:
"""Control: the default engine keeps the 💤 idle-resume status line."""
db = SessionDB(db_path=tmp_path / "state.db")
sid = "IDLE_LOUD"
db.create_session(sid, source="cli")
agent = _prep_idle_agent(db, sid)
# MagicMock would auto-create the hook attributes as truthy mocks; pin
# the default-engine surface explicitly.
agent.context_compressor.emit_automatic_compaction_status = True
del agent.context_compressor.get_automatic_compaction_status_message
events = []
agent.status_callback = lambda ev, msg: events.append((ev, msg))
_run_prologue(agent, _history())
agent.context_compressor.compress.assert_called_once()
assert any(
ev == "lifecycle" and "Resumed after" in str(msg) for ev, msg in events
), f"expected idle status line, got: {events}"
def test_idle_compaction_defers_to_held_compression_lock(tmp_path: Path) -> None:
"""An idle-triggered compress racing another path must sit the round out.
The per-session lock landed after the idle-compaction PR: when another
path (turn-triggered preflight, background-review fork) already holds the
lock, ``compress_context`` returns the input list unchanged. The idle
block must treat that skip as a strict no-op: no compressor call, no
rotation, no flush re-baseline, anchor untouched.
"""
db = SessionDB(db_path=tmp_path / "state.db")
sid = "IDLE_LOCKED"
db.create_session(sid, source="cli")
assert db.try_acquire_compression_lock(sid, "external_holder") is True
agent = _prep_idle_agent(db, sid)
history = _history()
ctx = _run_prologue(agent, history)
# Skipped: the compressor never ran and the session did not rotate.
agent.context_compressor.compress.assert_not_called()
assert agent.session_id == sid
# The external holder still owns the lock (we must not have stolen or
# released someone else's lease).
assert db.get_compression_lock_holder(sid) == "external_holder"
# Turn state untouched: full history + this turn's user message, anchor on
# the just-appended message, flush baseline not re-baselined to None-then-
# doubled semantics.
assert len(ctx.messages) == len(history) + 1
assert ctx.current_turn_user_idx == len(ctx.messages) - 1
assert ctx.messages[ctx.current_turn_user_idx]["content"] == "hello again"
def test_idle_compaction_respects_anti_thrash_breaker(tmp_path: Path) -> None:
"""A tripped ineffective-compression breaker must block the idle trigger.
The breaker lives in ``ContextCompressor._automatic_compression_blocked``
and is consulted by ``compress_context`` for every non-forced entrypoint.
The idle path is an automatic entrypoint, so two prior ineffective
compactions must silence it too.
"""
from agent.context_compressor import ContextCompressor
db = SessionDB(db_path=tmp_path / "state.db")
sid = "IDLE_THRASH"
db.create_session(sid, source="cli")
agent = _prep_idle_agent(db, sid)
with patch(
"agent.context_compressor.get_model_context_length", return_value=100_000
):
compressor = ContextCompressor(
model="test/model",
threshold_percent=0.85,
protect_first_n=2,
protect_last_n=2,
quiet_mode=True,
)
compressor.bind_session_state(db, sid)
# Trip the breaker durably (#54923: the strike counter now round-trips
# state.db, and the gate re-reads durable rows before honoring a block).
db.set_compression_ineffective_count(sid, 2)
compressor._ineffective_compression_count = 2 # breaker tripped
compressor.compress = MagicMock()
agent.context_compressor = compressor
ctx = _run_prologue(agent, _history())
compressor.compress.assert_not_called()
assert agent.session_id == sid
assert len(ctx.messages) == len(_history()) + 1
def test_idle_compaction_respects_persisted_failure_cooldown(
tmp_path: Path,
) -> None:
"""An active summary-failure cooldown must gate the idle trigger up front.
The idle predicate itself consults
``get_active_compression_failure_cooldown`` — with a persisted cooldown in
state.db the trigger must not even reach ``_compress_context``.
"""
from agent.context_compressor import ContextCompressor
db = SessionDB(db_path=tmp_path / "state.db")
sid = "IDLE_COOLDOWN"
db.create_session(sid, source="cli")
db.record_compression_failure_cooldown(sid, 4_000_000_000.0, "timeout")
agent = _prep_idle_agent(db, sid)
with patch(
"agent.context_compressor.get_model_context_length", return_value=100_000
):
compressor = ContextCompressor(
model="test/model",
threshold_percent=0.85,
protect_first_n=2,
protect_last_n=2,
quiet_mode=True,
)
compressor.bind_session_state(db, sid)
compressor.compress = MagicMock()
agent.context_compressor = compressor
agent._compress_context = MagicMock()
ctx = _run_prologue(agent, _history())
agent._compress_context.assert_not_called()
compressor.compress.assert_not_called()
assert agent.session_id == sid
assert len(ctx.messages) == len(_history()) + 1
def test_idle_compaction_disabled_by_default(tmp_path: Path) -> None:
"""With the default config (0) a huge idle gap must never trigger."""
db = SessionDB(db_path=tmp_path / "state.db")
sid = "IDLE_OFF"
db.create_session(sid, source="cli")
agent = _prep_idle_agent(db, sid, idle_after=0, idle_gap=10_000_000.0)
agent._compress_context = MagicMock()
ctx = _run_prologue(agent, _history())
agent._compress_context.assert_not_called()
agent.context_compressor.compress.assert_not_called()
assert agent.session_id == sid
assert len(ctx.messages) == len(_history()) + 1