Revert "Revert LruCache CacheManager changes for now"

This reverts commit ccd0a71.

Author: MadLittleMods

synapse/rest/client/sync.py

@@ -125,8 +125,7 @@ def __init__(self, hs: "HomeServer"):
         self._json_filter_cache: LruCache[str, bool] = LruCache(
             max_size=1000,
             cache_name="sync_valid_filter",
-            # TODO
-            # cache_manager=hs.get_cache_manager(),
+            cache_manager=hs.get_cache_manager(),
         )
 
         # Ratelimiter for presence updates, keyed by requester.

synapse/storage/databases/main/client_ips.py

@@ -436,8 +436,7 @@ def __init__(
         self.client_ip_last_seen = LruCache[Tuple[str, str, str], int](
             max_size=50000,
             cache_name="client_ip_last_seen",
-            # TODO
-            # cache_manager=hs.get_cache_manager(),
+            cache_manager=hs.get_cache_manager(),
         )
 
         if hs.config.worker.run_background_tasks and self.user_ips_max_age:

synapse/storage/databases/main/devices.py

@@ -1780,8 +1780,7 @@ def __init__(
             LruCache(
                 max_size=10000,
                 cache_name="device_id_exists",
-                # TODO
-                # cache_manager=hs.get_cache_manager(),
+                cache_manager=hs.get_cache_manager(),
             )
         )
 

synapse/storage/databases/main/event_federation.py

@@ -147,8 +147,7 @@ def __init__(
         self._event_auth_cache: LruCache[str, List[Tuple[str, int]]] = LruCache(
             500000,
             cache_name="_event_auth_cache",
-            # TODO
-            # cache_manager=hs.get_cache_manager(),
+            cache_manager=hs.get_cache_manager(),
             size_callback=len,
         )
 

synapse/util/caches/deferred_cache.py

@@ -44,6 +44,7 @@
 from twisted.python.failure import Failure
 
 from synapse.util.async_helpers import ObservableDeferred
+from synapse.util.caches import CacheManager
 from synapse.util.caches.lrucache import LruCache
 from synapse.util.caches.treecache import TreeCache, iterate_tree_cache_entry
 
@@ -80,6 +81,7 @@ class DeferredCache(Generic[KT, VT]):
     def __init__(
         self,
         name: str,
+        cache_manager: CacheManager,
         max_entries: int = 1000,
         tree: bool = False,
         iterable: bool = False,
@@ -89,6 +91,7 @@ def __init__(
         """
         Args:
             name: The name of the cache
+            cache_manager: The cache manager to handle metrics
             max_entries: Maximum amount of entries that the cache will hold
             tree: Use a TreeCache instead of a dict as the underlying cache type
             iterable: If True, count each item in the cached object as an entry,
@@ -114,6 +117,7 @@ def metrics_cb() -> None:
         self.cache: LruCache[KT, VT] = LruCache(
             max_size=max_entries,
             cache_name=name,
+            cache_manager=cache_manager,
             cache_type=cache_type,
             size_callback=(
                 (lambda d: len(cast(Sized, d)) or 1)

synapse/util/caches/lrucache.py

@@ -51,7 +51,7 @@
 from synapse.config import cache as cache_config
 from synapse.metrics.background_process_metrics import wrap_as_background_process
 from synapse.util import Clock, caches
-from synapse.util.caches import CacheMetric, EvictionReason
+from synapse.util.caches import CacheManager, CacheMetric, EvictionReason
 from synapse.util.caches.treecache import (
     TreeCache,
     iterate_tree_cache_entry,
@@ -379,11 +379,44 @@ class LruCache(Generic[KT, VT]):
     If cache_type=TreeCache, all keys must be tuples.
     """
 
+    # If you're providing in the `cache_name`, then you must provide the `cache_manager`
+    @overload
+    def __init__(
+        self,
+        max_size: int,
+        *,
+        cache_name: str,
+        cache_manager: CacheManager,
+        metrics_collection_callback: Optional[Callable[[], None]] = None,
+        cache_type: Type[Union[dict, TreeCache]] = dict,
+        size_callback: Optional[Callable[[VT], int]] = None,
+        apply_cache_factor_from_config: bool = True,
+        clock: Optional[Clock] = None,
+        prune_unread_entries: bool = True,
+        extra_index_cb: Optional[Callable[[KT, VT], KT]] = None,
+    ): ...
+
+    # If you're *not* providing in the `cache_name`, then you shouldn't provide the
+    # `cache_manager` or the `metrics_collection_callback`
+    @overload
+    def __init__(
+        self,
+        max_size: int,
+        *,
+        cache_type: Type[Union[dict, TreeCache]] = dict,
+        size_callback: Optional[Callable[[VT], int]] = None,
+        apply_cache_factor_from_config: bool = True,
+        clock: Optional[Clock] = None,
+        prune_unread_entries: bool = True,
+        extra_index_cb: Optional[Callable[[KT, VT], KT]] = None,
+    ): ...
+
     def __init__(
         self,
         max_size: int,
         *,
         cache_name: Optional[str] = None,
+        cache_manager: Optional[CacheManager] = None,
         metrics_collection_callback: Optional[Callable[[], None]] = None,
         cache_type: Type[Union[dict, TreeCache]] = dict,
         size_callback: Optional[Callable[[VT], int]] = None,
@@ -399,6 +432,9 @@ def __init__(
             cache_name: The name of this cache, for the prometheus metrics. If unset,
                 no metrics will be reported on this cache.
 
+            cache_manager: The cache manager to handle metrics. If unset, no metrics will be
+                reported on this cache.
+
                 Ignored if `cache_name` is `None`.
 
             metrics_collection_callback:
@@ -463,17 +499,15 @@ def __init__(
         # do yet when we get resized.
         self._on_resize: Optional[Callable[[], None]] = None
 
-        # TODO
-        # if cache_name is not None:
-        #     metrics: Optional[CacheMetric] = cache_manager.register_cache(
-        #         "lru_cache",
-        #         cache_name,
-        #         self,
-        #         collect_callback=metrics_collection_callback,
-        #     )
-        # else:
-        #     metrics = None
-        metrics: Optional[CacheMetric] = None
+        if cache_name is not None:
+            metrics: Optional[CacheMetric] = cache_manager.register_cache(
+                "lru_cache",
+                cache_name,
+                self,
+                collect_callback=metrics_collection_callback,
+            )
+        else:
+            metrics = None
 
         # this is exposed for access from outside this class
         self.metrics = metrics

tests/util/test_lrucache.py

@@ -99,6 +99,8 @@ def test_special_size(self) -> None:
         cache: LruCache = LruCache(
             10,
             cache_name="mycache",
+            # TODO
+            # cache_manager=TODO
         )
         self.assertEqual(cache.max_size, 100)