Merge pull request #519 from matrix-org/dbkr/treecache

Make LRU caching tree-based so subtrees of the cache can be invalidated cheaply.
This commit is contained in:
David Baker 2016-01-22 14:47:48 +00:00
commit 7a3fe48ba4
6 changed files with 236 additions and 26 deletions

View file

@ -40,14 +40,20 @@ class EventPushActionsStore(SQLBaseStore):
'actions': json.dumps(actions)
})
def f(txn):
for uid, _, __ in tuples:
txn.call_after(
self.get_unread_event_push_actions_by_room_for_user.invalidate_many,
(event.room_id, uid)
)
return self._simple_insert_many_txn(txn, "event_push_actions", values)
yield self.runInteraction(
"set_actions_for_event_and_users",
self._simple_insert_many_txn,
"event_push_actions",
values
f,
)
@cachedInlineCallbacks(num_args=3)
@cachedInlineCallbacks(num_args=3, lru=True, tree=True)
def get_unread_event_push_actions_by_room_for_user(
self, room_id, user_id, last_read_event_id
):
@ -98,6 +104,11 @@ class EventPushActionsStore(SQLBaseStore):
@defer.inlineCallbacks
def remove_push_actions_for_event_id(self, room_id, event_id):
def f(txn):
# Sad that we have to blow away the cache for the whole room here
txn.call_after(
self.get_unread_event_push_actions_by_room_for_user.invalidate_many,
(room_id,)
)
txn.execute(
"DELETE FROM event_push_actions WHERE room_id = ? AND event_id = ?",
(room_id, event_id)

View file

@ -17,6 +17,7 @@ import logging
from synapse.util.async import ObservableDeferred
from synapse.util import unwrapFirstError
from synapse.util.caches.lrucache import LruCache
from synapse.util.caches.treecache import TreeCache
from . import caches_by_name, DEBUG_CACHES, cache_counter
@ -36,9 +37,12 @@ _CacheSentinel = object()
class Cache(object):
def __init__(self, name, max_entries=1000, keylen=1, lru=True):
def __init__(self, name, max_entries=1000, keylen=1, lru=True, tree=False):
if lru:
self.cache = LruCache(max_size=max_entries)
cache_type = TreeCache if tree else dict
self.cache = LruCache(
max_size=max_entries, keylen=keylen, cache_type=cache_type
)
self.max_entries = None
else:
self.cache = OrderedDict()
@ -99,6 +103,15 @@ class Cache(object):
self.sequence += 1
self.cache.pop(key, None)
def invalidate_many(self, key):
self.check_thread()
if not isinstance(key, tuple):
raise TypeError(
"The cache key must be a tuple not %r" % (type(key),)
)
self.sequence += 1
self.cache.del_multi(key)
def invalidate_all(self):
self.check_thread()
self.sequence += 1
@ -122,7 +135,7 @@ class CacheDescriptor(object):
which can be used to insert values into the cache specifically, without
calling the calculation function.
"""
def __init__(self, orig, max_entries=1000, num_args=1, lru=True,
def __init__(self, orig, max_entries=1000, num_args=1, lru=True, tree=False,
inlineCallbacks=False):
self.orig = orig
@ -134,6 +147,7 @@ class CacheDescriptor(object):
self.max_entries = max_entries
self.num_args = num_args
self.lru = lru
self.tree = tree
self.arg_names = inspect.getargspec(orig).args[1:num_args+1]
@ -149,6 +163,7 @@ class CacheDescriptor(object):
max_entries=self.max_entries,
keylen=self.num_args,
lru=self.lru,
tree=self.tree,
)
def __get__(self, obj, objtype=None):
@ -200,6 +215,7 @@ class CacheDescriptor(object):
wrapped.invalidate = self.cache.invalidate
wrapped.invalidate_all = self.cache.invalidate_all
wrapped.invalidate_many = self.cache.invalidate_many
wrapped.prefill = self.cache.prefill
obj.__dict__[self.orig.__name__] = wrapped
@ -321,21 +337,23 @@ class CacheListDescriptor(object):
return wrapped
def cached(max_entries=1000, num_args=1, lru=True):
return lambda orig: CacheDescriptor(
orig,
max_entries=max_entries,
num_args=num_args,
lru=lru
)
def cachedInlineCallbacks(max_entries=1000, num_args=1, lru=False):
def cached(max_entries=1000, num_args=1, lru=True, tree=False):
return lambda orig: CacheDescriptor(
orig,
max_entries=max_entries,
num_args=num_args,
lru=lru,
tree=tree,
)
def cachedInlineCallbacks(max_entries=1000, num_args=1, lru=False, tree=False):
return lambda orig: CacheDescriptor(
orig,
max_entries=max_entries,
num_args=num_args,
lru=lru,
tree=tree,
inlineCallbacks=True,
)

View file

@ -17,11 +17,27 @@
from functools import wraps
import threading
from synapse.util.caches.treecache import TreeCache
def enumerate_leaves(node, depth):
if depth == 0:
yield node
else:
for n in node.values():
for m in enumerate_leaves(n, depth - 1):
yield m
class LruCache(object):
"""Least-recently-used cache."""
def __init__(self, max_size):
cache = {}
"""
Least-recently-used cache.
Supports del_multi only if cache_type=TreeCache
If cache_type=TreeCache, all keys must be tuples.
"""
def __init__(self, max_size, keylen=1, cache_type=dict):
cache = cache_type()
self.size = 0
list_root = []
list_root[:] = [list_root, list_root, None, None]
@ -44,6 +60,7 @@ class LruCache(object):
prev_node[NEXT] = node
next_node[PREV] = node
cache[key] = node
self.size += 1
def move_node_to_front(node):
prev_node = node[PREV]
@ -62,7 +79,7 @@ class LruCache(object):
next_node = node[NEXT]
prev_node[NEXT] = next_node
next_node[PREV] = prev_node
cache.pop(node[KEY], None)
self.size -= 1
@synchronized
def cache_get(key, default=None):
@ -81,8 +98,10 @@ class LruCache(object):
node[VALUE] = value
else:
add_node(key, value)
if len(cache) > max_size:
delete_node(list_root[PREV])
if self.size > max_size:
todelete = list_root[PREV]
delete_node(todelete)
cache.pop(todelete[KEY], None)
@synchronized
def cache_set_default(key, value):
@ -91,8 +110,10 @@ class LruCache(object):
return node[VALUE]
else:
add_node(key, value)
if len(cache) > max_size:
delete_node(list_root[PREV])
if self.size > max_size:
todelete = list_root[PREV]
delete_node(todelete)
cache.pop(todelete[KEY], None)
return value
@synchronized
@ -100,10 +121,22 @@ class LruCache(object):
node = cache.get(key, None)
if node:
delete_node(node)
cache.pop(node[KEY], None)
return node[VALUE]
else:
return default
@synchronized
def cache_del_multi(key):
"""
This will only work if constructed with cache_type=TreeCache
"""
popped = cache.pop(key)
if popped is None:
return
for leaf in enumerate_leaves(popped, keylen - len(key)):
delete_node(leaf)
@synchronized
def cache_clear():
list_root[NEXT] = list_root
@ -112,7 +145,7 @@ class LruCache(object):
@synchronized
def cache_len():
return len(cache)
return self.size
@synchronized
def cache_contains(key):
@ -123,6 +156,8 @@ class LruCache(object):
self.set = cache_set
self.setdefault = cache_set_default
self.pop = cache_pop
if cache_type is TreeCache:
self.del_multi = cache_del_multi
self.len = cache_len
self.contains = cache_contains
self.clear = cache_clear

View file

@ -0,0 +1,60 @@
SENTINEL = object()
class TreeCache(object):
"""
Tree-based backing store for LruCache. Allows subtrees of data to be deleted
efficiently.
Keys must be tuples.
"""
def __init__(self):
self.root = {}
def __setitem__(self, key, value):
return self.set(key, value)
def __contains__(self, key):
return self.get(key, SENTINEL) is not SENTINEL
def set(self, key, value):
node = self.root
for k in key[:-1]:
node = node.setdefault(k, {})
node[key[-1]] = value
def get(self, key, default=None):
node = self.root
for k in key[:-1]:
node = node.get(k, None)
if node is None:
return default
return node.get(key[-1], default)
def clear(self):
self.root = {}
def pop(self, key, default=None):
nodes = []
node = self.root
for k in key[:-1]:
node = node.get(k, None)
nodes.append(node) # don't add the root node
if node is None:
return default
popped = node.pop(key[-1], SENTINEL)
if popped is SENTINEL:
return default
node_and_keys = zip(nodes, key)
node_and_keys.reverse()
node_and_keys.append((self.root, None))
for i in range(len(node_and_keys) - 1):
n, k = node_and_keys[i]
if n:
break
node_and_keys[i+1][0].pop(k)
return popped

View file

@ -17,6 +17,7 @@
from .. import unittest
from synapse.util.caches.lrucache import LruCache
from synapse.util.caches.treecache import TreeCache
class LruCacheTestCase(unittest.TestCase):
@ -52,3 +53,22 @@ class LruCacheTestCase(unittest.TestCase):
cache["key"] = 1
self.assertEquals(cache.pop("key"), 1)
self.assertEquals(cache.pop("key"), None)
def test_del_multi(self):
cache = LruCache(4, 2, cache_type=TreeCache)
cache[("animal", "cat")] = "mew"
cache[("animal", "dog")] = "woof"
cache[("vehicles", "car")] = "vroom"
cache[("vehicles", "train")] = "chuff"
self.assertEquals(len(cache), 4)
self.assertEquals(cache.get(("animal", "cat")), "mew")
self.assertEquals(cache.get(("vehicles", "car")), "vroom")
cache.del_multi(("animal",))
self.assertEquals(len(cache), 2)
self.assertEquals(cache.get(("animal", "cat")), None)
self.assertEquals(cache.get(("animal", "dog")), None)
self.assertEquals(cache.get(("vehicles", "car")), "vroom")
self.assertEquals(cache.get(("vehicles", "train")), "chuff")
# Man from del_multi say "Yes".

View file

@ -0,0 +1,66 @@
# -*- coding: utf-8 -*-
# Copyright 2015, 2016 OpenMarket Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from .. import unittest
from synapse.util.caches.treecache import TreeCache
class TreeCacheTestCase(unittest.TestCase):
def test_get_set_onelevel(self):
cache = TreeCache()
cache[("a",)] = "A"
cache[("b",)] = "B"
self.assertEquals(cache.get(("a",)), "A")
self.assertEquals(cache.get(("b",)), "B")
def test_pop_onelevel(self):
cache = TreeCache()
cache[("a",)] = "A"
cache[("b",)] = "B"
self.assertEquals(cache.pop(("a",)), "A")
self.assertEquals(cache.pop(("a",)), None)
self.assertEquals(cache.get(("b",)), "B")
def test_get_set_twolevel(self):
cache = TreeCache()
cache[("a", "a")] = "AA"
cache[("a", "b")] = "AB"
cache[("b", "a")] = "BA"
self.assertEquals(cache.get(("a", "a")), "AA")
self.assertEquals(cache.get(("a", "b")), "AB")
self.assertEquals(cache.get(("b", "a")), "BA")
def test_pop_twolevel(self):
cache = TreeCache()
cache[("a", "a")] = "AA"
cache[("a", "b")] = "AB"
cache[("b", "a")] = "BA"
self.assertEquals(cache.pop(("a", "a")), "AA")
self.assertEquals(cache.get(("a", "a")), None)
self.assertEquals(cache.get(("a", "b")), "AB")
self.assertEquals(cache.pop(("b", "a")), "BA")
self.assertEquals(cache.pop(("b", "a")), None)
def test_pop_mixedlevel(self):
cache = TreeCache()
cache[("a", "a")] = "AA"
cache[("a", "b")] = "AB"
cache[("b", "a")] = "BA"
self.assertEquals(cache.get(("a", "a")), "AA")
cache.pop(("a",))
self.assertEquals(cache.get(("a", "a")), None)
self.assertEquals(cache.get(("a", "b")), None)
self.assertEquals(cache.get(("b", "a")), "BA")