forked-synapse/synapse/util/caches/__init__.py
2017-01-17 17:04:46 +00:00

100 lines
2.5 KiB
Python

# -*- 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.
import synapse.metrics
from lrucache import LruCache
import os
CACHE_SIZE_FACTOR = float(os.environ.get("SYNAPSE_CACHE_FACTOR", 0.1))
DEBUG_CACHES = False
metrics = synapse.metrics.get_metrics_for("synapse.util.caches")
caches_by_name = {}
# cache_counter = metrics.register_cache(
# "cache",
# lambda: {(name,): len(caches_by_name[name]) for name in caches_by_name.keys()},
# labels=["name"],
# )
def register_cache(name, cache):
caches_by_name[name] = cache
return metrics.register_cache(
"cache",
lambda: len(cache),
name,
)
_string_cache = LruCache(int(100000 * CACHE_SIZE_FACTOR))
_stirng_cache_metrics = register_cache("string_cache", _string_cache)
KNOWN_KEYS = {
key: key for key in
(
"auth_events",
"content",
"depth",
"event_id",
"hashes",
"origin",
"origin_server_ts",
"prev_events",
"room_id",
"sender",
"signatures",
"state_key",
"type",
"unsigned",
"user_id",
)
}
def intern_string(string):
"""Takes a (potentially) unicode string and interns using custom cache
"""
new_str = _string_cache.setdefault(string, string)
if new_str is string:
_stirng_cache_metrics.inc_hits()
else:
_stirng_cache_metrics.inc_misses()
return new_str
def intern_dict(dictionary):
"""Takes a dictionary and interns well known keys and their values
"""
return {
KNOWN_KEYS.get(key, key): _intern_known_values(key, value)
for key, value in dictionary.items()
}
def _intern_known_values(key, value):
intern_str_keys = ("event_id", "room_id")
intern_unicode_keys = ("sender", "user_id", "type", "state_key")
if key in intern_str_keys:
return intern(value.encode('ascii'))
if key in intern_unicode_keys:
return intern_string(value)
return value