MatrixSynapse/synapse/config/cache.py

119 lines
4.3 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2019 Matrix.org Foundation C.I.C.
#
# 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 os
from typing import Callable, Dict, Optional, Union
from ._base import Config, ConfigError
_CACHES = {}
_CACHE_PREFIX = "SYNAPSE_CACHE_FACTOR"
# Wrap all global vars into a single object to eliminate `global` calls
CACHE_PROPERTIES: Dict[str, Union[str, float, Optional[Callable[[], None]]]] = {
"prefix": _CACHE_PREFIX,
"default_size_factor": float(os.environ.get(_CACHE_PREFIX, 0.5)),
# Callback to ensure that all caches are the correct size, registered when the
# configuration has been loaded.
"ensure_correct_cache_sizing": None,
}
def add_resizable_cache(cache_name, cache_resize_callback):
_CACHES[cache_name.lower()] = cache_resize_callback
if CACHE_PROPERTIES["ensure_correct_cache_sizing"]:
CACHE_PROPERTIES["ensure_correct_cache_sizing"]()
class CacheConfig(Config):
section = "caches"
_environ = os.environ
@staticmethod
def _reset():
"""Resets the caches to their defaults.
Used for tests.
"""
CACHE_PROPERTIES["default_size_factor"] = float(
os.environ.get(_CACHE_PREFIX, 0.5)
)
CACHE_PROPERTIES["ensure_correct_cache_sizing"] = None
_CACHES.clear()
def generate_config_section(self, **kwargs):
return """\
# Cache configuration
#
# 'global_factor' controls the global cache factor. This overrides the
# "SYNAPSE_CACHE_FACTOR" environment variable.
#
# 'per_cache_factors' is a dictionary of cache name to cache factor for that
# individual cache.
#
#caches:
# global_factor: 0.5
# per_cache_factors:
# get_users_who_share_room_with_user: 2
#
"""
def read_config(self, config, **kwargs):
self.event_cache_size = self.parse_size(config.get("event_cache_size", "10K"))
cache_config = config.get("caches", {})
self.global_factor = cache_config.get(
"global_factor", CACHE_PROPERTIES["default_cache_size_factor"]
)
if not isinstance(self.global_factor, (int, float)):
raise ConfigError("caches.global_factor must be a number.")
# Set the global one so that it's reflected in new caches
CACHE_PROPERTIES["default_cache_size_factor"] = self.global_factor
# Load cache factors from the environment, but override them with the
# ones in the config file if they exist
individual_factors = {
key[len(CACHE_PROPERTIES["prefix"]) + 1 :].lower(): float(val)
for key, val in self._environ.items()
if key.startswith(CACHE_PROPERTIES["prefix"] + "_")
}
individual_factors_config = cache_config.get("per_cache_factors", {}) or {}
if not isinstance(individual_factors_config, dict):
raise ConfigError("caches.per_cache_factors must be a dictionary")
individual_factors.update(individual_factors_config)
self.cache_factors = dict() # type: Dict[str, float]
for cache, factor in individual_factors.items():
if not isinstance(factor, (int, float)):
raise ConfigError(
"caches.per_cache_factors.%s must be a number" % (cache.lower(),)
)
self.cache_factors[cache.lower()] = factor
# Register the global callback so that the individual cache sizes get set.
def ensure_cache_sizes():
for cache_name, callback in _CACHES.items():
new_factor = self.cache_factors.get(cache_name, self.global_factor)
callback(new_factor)
CACHE_PROPERTIES["ensure_correct_cache_sizing"] = ensure_cache_sizes
CACHE_PROPERTIES["ensure_correct_cache_sizing"]()