diff options
Diffstat (limited to 'synapse/util')
| -rw-r--r-- | synapse/util/async_helpers.py | 14 | ||||
| -rw-r--r-- | synapse/util/caches/ttlcache.py | 161 | ||||
| -rw-r--r-- | synapse/util/logcontext.py | 5 | ||||
| -rw-r--r-- | synapse/util/stringutils.py | 39 |
4 files changed, 211 insertions, 8 deletions
diff --git a/synapse/util/async_helpers.py b/synapse/util/async_helpers.py index ec7b2c9672..f0e4a0e10c 100644 --- a/synapse/util/async_helpers.py +++ b/synapse/util/async_helpers.py @@ -201,7 +201,7 @@ class Linearizer(object): if entry[0] >= self.max_count: res = self._await_lock(key) else: - logger.info( + logger.debug( "Acquired uncontended linearizer lock %r for key %r", self.name, key, ) entry[0] += 1 @@ -215,7 +215,7 @@ class Linearizer(object): try: yield finally: - logger.info("Releasing linearizer lock %r for key %r", self.name, key) + logger.debug("Releasing linearizer lock %r for key %r", self.name, key) # We've finished executing so check if there are any things # blocked waiting to execute and start one of them @@ -247,7 +247,7 @@ class Linearizer(object): """ entry = self.key_to_defer[key] - logger.info( + logger.debug( "Waiting to acquire linearizer lock %r for key %r", self.name, key, ) @@ -255,7 +255,7 @@ class Linearizer(object): entry[1][new_defer] = 1 def cb(_r): - logger.info("Acquired linearizer lock %r for key %r", self.name, key) + logger.debug("Acquired linearizer lock %r for key %r", self.name, key) entry[0] += 1 # if the code holding the lock completes synchronously, then it @@ -273,7 +273,7 @@ class Linearizer(object): def eb(e): logger.info("defer %r got err %r", new_defer, e) if isinstance(e, CancelledError): - logger.info( + logger.debug( "Cancelling wait for linearizer lock %r for key %r", self.name, key, ) @@ -387,12 +387,14 @@ def timeout_deferred(deferred, timeout, reactor, on_timeout_cancel=None): deferred that wraps and times out the given deferred, correctly handling the case where the given deferred's canceller throws. + (See https://twistedmatrix.com/trac/ticket/9534) + NOTE: Unlike `Deferred.addTimeout`, this function returns a new deferred Args: deferred (Deferred) timeout (float): Timeout in seconds - reactor (twisted.internet.reactor): The twisted reactor to use + reactor (twisted.interfaces.IReactorTime): The twisted reactor to use on_timeout_cancel (callable): A callable which is called immediately after the deferred times out, and not if this deferred is otherwise cancelled before the timeout. diff --git a/synapse/util/caches/ttlcache.py b/synapse/util/caches/ttlcache.py new file mode 100644 index 0000000000..5ba1862506 --- /dev/null +++ b/synapse/util/caches/ttlcache.py @@ -0,0 +1,161 @@ +# -*- 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 logging +import time + +import attr +from sortedcontainers import SortedList + +from synapse.util.caches import register_cache + +logger = logging.getLogger(__name__) + +SENTINEL = object() + + +class TTLCache(object): + """A key/value cache implementation where each entry has its own TTL""" + + def __init__(self, cache_name, timer=time.time): + # map from key to _CacheEntry + self._data = {} + + # the _CacheEntries, sorted by expiry time + self._expiry_list = SortedList() + + self._timer = timer + + self._metrics = register_cache("ttl", cache_name, self) + + def set(self, key, value, ttl): + """Add/update an entry in the cache + + Args: + key: key for this entry + value: value for this entry + ttl (float): TTL for this entry, in seconds + """ + expiry = self._timer() + ttl + + self.expire() + e = self._data.pop(key, SENTINEL) + if e != SENTINEL: + self._expiry_list.remove(e) + + entry = _CacheEntry(expiry_time=expiry, key=key, value=value) + self._data[key] = entry + self._expiry_list.add(entry) + + def get(self, key, default=SENTINEL): + """Get a value from the cache + + Args: + key: key to look up + default: default value to return, if key is not found. If not set, and the + key is not found, a KeyError will be raised + + Returns: + value from the cache, or the default + """ + self.expire() + e = self._data.get(key, SENTINEL) + if e == SENTINEL: + self._metrics.inc_misses() + if default == SENTINEL: + raise KeyError(key) + return default + self._metrics.inc_hits() + return e.value + + def get_with_expiry(self, key): + """Get a value, and its expiry time, from the cache + + Args: + key: key to look up + + Returns: + Tuple[Any, float]: the value from the cache, and the expiry time + + Raises: + KeyError if the entry is not found + """ + self.expire() + try: + e = self._data[key] + except KeyError: + self._metrics.inc_misses() + raise + self._metrics.inc_hits() + return e.value, e.expiry_time + + def pop(self, key, default=SENTINEL): + """Remove a value from the cache + + If key is in the cache, remove it and return its value, else return default. + If default is not given and key is not in the cache, a KeyError is raised. + + Args: + key: key to look up + default: default value to return, if key is not found. If not set, and the + key is not found, a KeyError will be raised + + Returns: + value from the cache, or the default + """ + self.expire() + e = self._data.pop(key, SENTINEL) + if e == SENTINEL: + self._metrics.inc_misses() + if default == SENTINEL: + raise KeyError(key) + return default + self._expiry_list.remove(e) + self._metrics.inc_hits() + return e.value + + def __getitem__(self, key): + return self.get(key) + + def __delitem__(self, key): + self.pop(key) + + def __contains__(self, key): + return key in self._data + + def __len__(self): + self.expire() + return len(self._data) + + def expire(self): + """Run the expiry on the cache. Any entries whose expiry times are due will + be removed + """ + now = self._timer() + while self._expiry_list: + first_entry = self._expiry_list[0] + if first_entry.expiry_time - now > 0.0: + break + del self._data[first_entry.key] + del self._expiry_list[0] + + +@attr.s(frozen=True, slots=True) +class _CacheEntry(object): + """TTLCache entry""" + # expiry_time is the first attribute, so that entries are sorted by expiry. + expiry_time = attr.ib() + key = attr.ib() + value = attr.ib() diff --git a/synapse/util/logcontext.py b/synapse/util/logcontext.py index 4c6e92beb8..311b49e18a 100644 --- a/synapse/util/logcontext.py +++ b/synapse/util/logcontext.py @@ -285,7 +285,10 @@ class LoggingContext(object): self.alive = False # if we have a parent, pass our CPU usage stats on - if self.parent_context is not None: + if ( + self.parent_context is not None + and hasattr(self.parent_context, '_resource_usage') + ): self.parent_context._resource_usage += self._resource_usage # reset them in case we get entered again diff --git a/synapse/util/stringutils.py b/synapse/util/stringutils.py index 6f318c6a29..fdcb375f95 100644 --- a/synapse/util/stringutils.py +++ b/synapse/util/stringutils.py @@ -16,7 +16,8 @@ import random import string -from six import PY3 +import six +from six import PY2, PY3 from six.moves import range _string_with_symbols = ( @@ -71,3 +72,39 @@ def to_ascii(s): return s.encode("ascii") except UnicodeEncodeError: return s + + +def exception_to_unicode(e): + """Helper function to extract the text of an exception as a unicode string + + Args: + e (Exception): exception to be stringified + + Returns: + unicode + """ + # urgh, this is a mess. The basic problem here is that psycopg2 constructs its + # exceptions with PyErr_SetString, with a (possibly non-ascii) argument. str() will + # then produce the raw byte sequence. Under Python 2, this will then cause another + # error if it gets mixed with a `unicode` object, as per + # https://github.com/matrix-org/synapse/issues/4252 + + # First of all, if we're under python3, everything is fine because it will sort this + # nonsense out for us. + if not PY2: + return str(e) + + # otherwise let's have a stab at decoding the exception message. We'll circumvent + # Exception.__str__(), which would explode if someone raised Exception(u'non-ascii') + # and instead look at what is in the args member. + + if len(e.args) == 0: + return u"" + elif len(e.args) > 1: + return six.text_type(repr(e.args)) + + msg = e.args[0] + if isinstance(msg, bytes): + return msg.decode('utf-8', errors='replace') + else: + return msg |