diff options
-rw-r--r-- | synapse/util/caches/dictionary_cache.py | 6 | ||||
-rw-r--r-- | synapse/util/caches/lrucache.py | 15 |
2 files changed, 16 insertions, 5 deletions
diff --git a/synapse/util/caches/dictionary_cache.py b/synapse/util/caches/dictionary_cache.py index d4105822b3..1709e8b429 100644 --- a/synapse/util/caches/dictionary_cache.py +++ b/synapse/util/caches/dictionary_cache.py @@ -132,9 +132,13 @@ class DictionaryCache(object): self._update_or_insert(key, value, known_absent) def _update_or_insert(self, key, value, known_absent): - entry = self.cache.setdefault(key, DictionaryEntry(False, set(), {})) + # We pop and reinsert as we need to tell the cache the size may have + # changed + + entry = self.cache.pop(key, DictionaryEntry(False, set(), {})) entry.value.update(value) entry.known_absent.update(known_absent) + self.cache[key] = entry def _insert(self, key, value, known_absent): self.cache[key] = DictionaryEntry(True, known_absent, value) diff --git a/synapse/util/caches/lrucache.py b/synapse/util/caches/lrucache.py index f088dd430e..1c5a982094 100644 --- a/synapse/util/caches/lrucache.py +++ b/synapse/util/caches/lrucache.py @@ -154,14 +154,21 @@ class LruCache(object): def cache_set(key, value, callbacks=[]): node = cache.get(key, None) if node is not None: - if value != node.value: + # We sometimes store large objects, e.g. dicts, which cause + # the inequality check to take a long time. So let's only do + # the check if we have some callbacks to call. + if node.callbacks and value != node.value: for cb in node.callbacks: cb() node.callbacks.clear() - if size_callback: - cached_cache_len[0] -= size_callback(node.value) - cached_cache_len[0] += size_callback(value) + # We don't bother to protect this by value != node.value as + # generally size_callback will be cheap compared with equality + # checks. (For example, taking the size of two dicts is quicker + # than comparing them for equality.) + if size_callback: + cached_cache_len[0] -= size_callback(node.value) + cached_cache_len[0] += size_callback(value) node.callbacks.update(callbacks) |