mirror of
https://github.com/matrix-org/dendrite.git
synced 2024-11-22 22:31:56 -06:00
60 lines
3 KiB
Markdown
60 lines
3 KiB
Markdown
# RoomServer
|
|
|
|
|
|
## RoomServer Internals
|
|
|
|
### Numeric IDs
|
|
|
|
To save space matrix string identifiers are mapped to local numeric IDs.
|
|
The numeric IDs are more efficient to manipulate and use less space to store.
|
|
The numeric IDs are never exposed in the API the room server exposes.
|
|
The numeric IDs are converted to string IDs before they leave the room server.
|
|
The numeric ID for a string ID is never 0 to avoid being confused with go's
|
|
default zero value.
|
|
Zero is used to indicate that there was no corresponding string ID.
|
|
Well-known event types and event state keys are preassigned numeric IDs.
|
|
|
|
### State Snapshot Storage
|
|
|
|
The room server stores the state of the matrix room at each event.
|
|
For efficiency the state is stored as blocks of 3-tuples of numeric IDs for the
|
|
event type, event state key and event ID. For further efficiency the state
|
|
snapshots are stored as the combination of up to 64 these blocks. This allows
|
|
blocks of the room state to be reused in multiple snapshots.
|
|
|
|
The resulting database tables look something like this:
|
|
|
|
+-------------------------------------------------------------------+
|
|
| Events |
|
|
+---------+-------------------+------------------+------------------+
|
|
| EventNID| EventTypeNID | EventStateKeyNID | StateSnapshotNID |
|
|
+---------+-------------------+------------------+------------------+
|
|
| 1 | m.room.create 1 | "" 1 | <nil> 0 |
|
|
| 2 | m.room.member 2 | "@user:foo" 2 | <nil> 0 |
|
|
| 3 | m.room.member 2 | "@user:bar" 3 | {1,2} 1 |
|
|
| 4 | m.room.message 3 | <nil> 0 | {1,2,3} 2 |
|
|
| 5 | m.room.member 2 | "@user:foo" 2 | {1,2,3} 2 |
|
|
| 6 | m.room.message 3 | <nil> 0 | {1,3,6} 3 |
|
|
+---------+-------------------+------------------+------------------+
|
|
|
|
+----------------------------------------+
|
|
| State Snapshots |
|
|
+-----------------------+----------------+
|
|
| EventStateSnapshotNID | StateBlockNIDs |
|
|
+-----------------------+----------------|
|
|
| 1 | {1} |
|
|
| 2 | {1,2} |
|
|
| 3 | {1,2,3} |
|
|
+-----------------------+----------------+
|
|
|
|
+-----------------------------------------------------------------+
|
|
| State Blocks |
|
|
+---------------+-------------------+------------------+----------+
|
|
| StateBlockNID | EventTypeNID | EventStateKeyNID | EventNID |
|
|
+---------------+-------------------+------------------+----------+
|
|
| 1 | m.room.create 1 | "" 1 | 1 |
|
|
| 1 | m.room.member 2 | "@user:foo" 2 | 2 |
|
|
| 2 | m.room.member 2 | "@user:bar" 3 | 3 |
|
|
| 3 | m.room.member 2 | "@user:foo" 2 | 6 |
|
|
+---------------+-------------------+------------------+----------+
|