Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Improve perf of sync device lists #17191

Merged
merged 2 commits into from
May 14, 2024
Merged

Improve perf of sync device lists #17191

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
21b63c4
Improve perf of sync device lists
erikjohnston May 14, 2024
ca001e8
Newsfile
erikjohnston May 14, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions changelog.d/17191.misc
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
Improve performance of calculating device lists changes in `/sync`.
37 changes: 6 additions & 31 deletions synapse/handlers/sync.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1803,38 +1803,13 @@ async def _generate_sync_entry_for_device_list(

# Step 1a, check for changes in devices of users we share a room
# with
#
# We do this in two different ways depending on what we have cached.
# If we already have a list of all the user that have changed since
# the last sync then it's likely more efficient to compare the rooms
# they're in with the rooms the syncing user is in.
#
# If we don't have that info cached then we get all the users that
# share a room with our user and check if those users have changed.
cache_result = self.store.get_cached_device_list_changes(
since_token.device_list_key
)
if cache_result.hit:
changed_users = cache_result.entities

result = await self.store.get_rooms_for_users(changed_users)

for changed_user_id, entries in result.items():
# Check if the changed user shares any rooms with the user,
# or if the changed user is the syncing user (as we always
# want to include device list updates of their own devices).
if user_id == changed_user_id or any(
rid in joined_rooms for rid in entries
):
users_that_have_changed.add(changed_user_id)
else:
users_that_have_changed = (
await self._device_handler.get_device_changes_in_shared_rooms(
user_id,
sync_result_builder.joined_room_ids,
from_token=since_token,
)
users_that_have_changed = (
await self._device_handler.get_device_changes_in_shared_rooms(
user_id,
sync_result_builder.joined_room_ids,
from_token=since_token,
)
)

# Step 1b, check for newly joined rooms
for room_id in newly_joined_rooms:
Expand Down
17 changes: 2 additions & 15 deletions synapse/storage/databases/main/devices.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -70,10 +70,7 @@
from synapse.util import json_decoder, json_encoder
from synapse.util.caches.descriptors import cached, cachedList
from synapse.util.caches.lrucache import LruCache
from synapse.util.caches.stream_change_cache import (
AllEntitiesChangedResult,
StreamChangeCache,
)
from synapse.util.caches.stream_change_cache import StreamChangeCache
from synapse.util.cancellation import cancellable
from synapse.util.iterutils import batch_iter
from synapse.util.stringutils import shortstr
Expand Down Expand Up @@ -832,16 +829,6 @@ async def get_cached_devices_for_user(
)
return {device[0]: db_to_json(device[1]) for device in devices}

def get_cached_device_list_changes(
self,
from_key: int,
) -> AllEntitiesChangedResult:
"""Get set of users whose devices have changed since `from_key`, or None
if that information is not in our cache.
"""

return self._device_list_stream_cache.get_all_entities_changed(from_key)

@cancellable
async def get_all_devices_changed(
self,
Expand Down Expand Up @@ -1475,7 +1462,7 @@ async def get_device_list_changes_in_rooms(

sql = """
SELECT DISTINCT user_id FROM device_lists_changes_in_room
WHERE {clause} AND stream_id >= ?
WHERE {clause} AND stream_id > ?
Copy link
Member Author

@erikjohnston erikjohnston May 14, 2024 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This is actually a bug that we didn't catch as we didn't test this code path much. I don't think its much of a problem, we'll just keep sending down the same device list repeatedly until the stream ID increments.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Good catch!

"""

def _get_device_list_changes_in_rooms_txn(
Expand Down
Loading