Commit Graph

104 Commits

Author SHA1 Message Date
Richard van der Hoff 01afc563c3 Fix overzealous cache invalidation
Fixes an issue where a cache invalidation would invalidate *all* pending
entries, rather than just the entry that we intended to invalidate.
2018-04-05 16:24:04 +01:00
Erik Johnston 9a0d783c11 Add comments 2018-03-19 11:35:53 +00:00
Erik Johnston 7c7706f42b Fix bug where state cache used lots of memory
The state cache bases its size on the sum of the size of entries. The
size of the entry is calculated once on insertion, so it is important
that the size of entries does not change.

The DictionaryCache modified the entries size, which caused the state
cache to incorrectly think it was smaller than it actually was.
2018-03-15 15:46:54 +00:00
Richard van der Hoff bc496df192 report metrics on number of cache evictions 2018-02-05 15:34:01 +00:00
Erik Johnston 495f075b41 Increase default cache factor size. 2017-07-04 09:58:32 +01:00
Erik Johnston b5e8d529e6 Define CACHE_SIZE_FACTOR once 2017-07-04 09:56:44 +01:00
Erik Johnston c72058bcc6 Use an ExpiringCache for storing registration sessions
This is because pruning them was a significant performance drain on
matrix.org
2017-06-29 14:08:37 +01:00
Erik Johnston efc2b7db95 Rewrite conditional 2017-06-09 13:35:15 +01:00
Erik Johnston eed59dcc1e Fix has_any_entity_changed
Occaisonally has_any_entity_changed would throw the error: "Set changed
size during iteration" when taking the max of the `sorteddict`. While
its uncertain how that happens, its quite inefficient to iterate over
the entire dict anyway so we change to using the more traditional
`bisect_*` functions.
2017-06-09 11:44:01 +01:00
Erik Johnston 304880d185 Add stream change cache 2017-05-31 15:46:36 +01:00
Erik Johnston bd7bb5df71 Pull out if statement from for loop 2017-05-22 15:12:19 +01:00
Erik Johnston e3417a06e2 Update list cache to handle one arg case
We update the normal cache descriptors to handle caches with a single
argument specially so that the key wasn't a 1-tuple. We need to update
the cache list to be aware of this.
2017-05-22 15:04:42 +01:00
Erik Johnston bbfe4e996c Make get_state_groups_from_groups faster.
Most of the time was spent copying a dict to filter out sentinel values
that indicated that keys did not exist in the dict. The sentinel values
were added to ensure that we cached the non-existence of keys.

By updating DictionaryCache to keep track of which keys were known to
not exist itself we can remove a dictionary copy.
2017-05-17 15:12:15 +01:00
Erik Johnston ffad4fe35b Don't update event cache hit ratio from get_joined_users
Otherwise the hit ration of plain get_events gets completely skewed by
calls to get_joined_users* functions.
2017-05-08 16:06:17 +01:00
Erik Johnston d2d8ed4884 Optimise caches with single key 2017-05-04 14:18:46 +01:00
Erik Johnston efab1dadde Remove DEBUG_CACHES 2017-04-25 10:54:09 +01:00
Erik Johnston 119cb9bbcf Reduce cache size by not storing deferreds
Currently the cache descriptors store deferreds rather than raw values,
this is a simple way of triggering only one database hit and sharing the
result if two callers attempt to get the same value.

However, there are a few caches that simply store a mapping from string
to string (or int). These caches can have a large number of entries,
under the assumption that each entry is small. However, the size of a
deferred (specifically the size of ObservableDeferred) is signigicantly
larger than that of the raw value, 2kb vs 32b.

This PR therefore changes the cache descriptors to store the raw values
rather than the deferreds.

As a side effect cached storage function now either return a deferred or
the actual value, as the cached list decriptor already does. This is
fine as we always end up just yield'ing on the returned value
eventually, which handles that case correctly.
2017-04-25 10:23:11 +01:00
Erik Johnston d134d0935e Only intern ascii strings 2017-04-24 14:07:48 +01:00
Erik Johnston 4d17add8de Remove unused instance variable 2017-03-31 09:38:27 +01:00
Erik Johnston 6194a64ae9 Doc new instance variables 2017-03-30 14:19:10 +01:00
Erik Johnston 014fee93b3 Manually calculate cache key as getcallargs is expensive
This is because getcallargs recomputes the getargspec, amongst other
things, which we don't need to do as its already been done
2017-03-30 14:14:46 +01:00
Erik Johnston 86780a8bc3 Don't convert to deferreds when not necessary 2017-03-30 14:14:36 +01:00
Richard van der Hoff f9b4bb05e0 Fix the logcontext handling in the cache wrappers (#2077)
The cache wrappers had a habit of leaking the logcontext into the reactor while
the lookup function was running, and then not restoring it correctly when the
lookup function had completed. It's all the fault of
`preserve_context_over_{fn,deferred}` which are basically a bit broken.
2017-03-30 13:22:24 +01:00
Richard van der Hoff 95f21c7a66 Fix caching of remote servers' signature keys
The `@cached` decorator on `KeyStore._get_server_verify_key` was missing
its `num_args` parameter, which meant that it was returning the wrong key for
any server which had more than one recorded key.

By way of a fix, change the default for `num_args` to be *all* arguments. To
implement that, factor out a common base class for `CacheDescriptor` and `CacheListDescriptor`.
2017-03-22 15:11:30 +00:00
Richard van der Hoff 29ed09e80a Fix assertion to stop transaction queue getting wedged
... and update some docstrings to correctly reflect the types being used.

get_new_device_msgs_for_remote can return a long under some circumstances,
which was being stored in last_device_list_stream_id_by_dest, and was then
upsetting things on the next loop.
2017-03-15 12:16:55 +00:00
Erik Johnston 3545e17f43 Add setdefault key to ExpiringCache 2017-03-10 10:30:49 +00:00
Erik Johnston 6b61060b51 Comment 2017-02-02 14:47:15 +00:00
Erik Johnston 9efcc3f3be Comment 2017-02-02 13:50:22 +00:00
Erik Johnston c430111d0e Update LruCache size estimate on clear 2017-01-18 14:55:23 +00:00
Erik Johnston 380dba1020 Measure metrics of string_cache 2017-01-17 17:04:46 +00:00
Erik Johnston 37b4c7d8a9 Fix typo in return type 2017-01-17 14:43:32 +00:00
Erik Johnston d6c75cb7c2 Rename and comment tree_to_leaves_iterator 2017-01-17 11:47:03 +00:00
Erik Johnston 1ccd5676e3 Remove needless call to evict() 2017-01-17 11:42:26 +00:00
Erik Johnston f85b6ca494 Speed up cache size calculation
Instead of calculating the size of the cache repeatedly, which can take
a long time now that it can use a callback, instead cache the size and
update that on insertion and deletion.

This requires changing the cache descriptors to have two caches, one for
pending deferreds and the other for the actual values. There's no reason
to evict from the pending deferreds as they won't take up any more
memory.
2017-01-17 11:18:13 +00:00
Erik Johnston 6d00213e80 Use OrderedDict in ExpiringCache 2017-01-16 15:33:22 +00:00
Erik Johnston 46aebbbcbf Add support for 'iterable' to ExpiringCache 2017-01-16 14:57:23 +00:00
Erik Johnston 2fae34bd2c Optionally measure size of cache by sum of length of values 2017-01-13 17:46:17 +00:00
Erik Johnston 955f34d23e Change get_pos_of_last_change to return upper bound 2016-09-15 15:12:07 +01:00
Erik Johnston cb3edec6af Use stream_change cache to make get_forward_extremeties_for_room cache more effective 2016-09-15 14:28:13 +01:00
Erik Johnston 45fd2c8942 Ensure invalidation list does not grow unboundedly 2016-08-19 16:09:16 +01:00
Erik Johnston c0d7d9d642 Rename to on_invalidate 2016-08-19 15:13:58 +01:00
Erik Johnston dc76a3e909 Make cache_context an explicit option 2016-08-19 15:02:38 +01:00
Erik Johnston ba214a5e32 Remove lru option 2016-08-19 14:17:11 +01:00
Erik Johnston 4161ff2fc4 Add concept of cache contexts 2016-08-19 14:17:07 +01:00
Erik Johnston 248e6770ca Cache federation state responses 2016-07-21 10:30:12 +01:00
Erik Johnston 3b096c5f5c Merge branch 'erikj/cache_perf' of github.com:matrix-org/synapse into develop 2016-06-03 12:00:33 +01:00
Erik Johnston 58a224a651 Pull out update_results_dict 2016-06-03 11:47:07 +01:00
Erik Johnston 73c7112433 Change CacheMetrics to be quicker
We change it so that each cache has an individual CacheMetric, instead
of having one global CacheMetric. This means that when a cache tries to
increment a counter it does not need to go through so many indirections.
2016-06-03 11:26:52 +01:00
Erik Johnston e043ede4a2 Small optimisation to CacheListDescriptor 2016-06-03 11:19:22 +01:00
Erik Johnston 597013caa5 Make cachedList go a bit faster 2016-06-03 11:13:29 +01:00