Migrate stream_ordering to a bigint (#10264)

* Move background update names out to a separate class

`EventsBackgroundUpdatesStore` gets inherited and we don't really want to
further pollute the namespace.

* Migrate stream_ordering to a bigint

* changelog
This commit is contained in:
Richard van der Hoff 2021-06-29 11:25:34 +01:00 committed by GitHub
parent a0ed0f363e
commit 60efc51a2b
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
4 changed files with 163 additions and 16 deletions

1
changelog.d/10264.bugfix Normal file
View file

@ -0,0 +1 @@
Fix a long-standing bug where Synapse would return errors after 2<sup>31</sup> events were handled by the server.

View file

@ -29,6 +29,25 @@ from synapse.types import JsonDict
logger = logging.getLogger(__name__)
_REPLACE_STREAM_ORDRING_SQL_COMMANDS = (
# there should be no leftover rows without a stream_ordering2, but just in case...
"UPDATE events SET stream_ordering2 = stream_ordering WHERE stream_ordering2 IS NULL",
# finally, we can drop the rule and switch the columns
"DROP RULE populate_stream_ordering2 ON events",
"ALTER TABLE events DROP COLUMN stream_ordering",
"ALTER TABLE events RENAME COLUMN stream_ordering2 TO stream_ordering",
)
class _BackgroundUpdates:
EVENT_ORIGIN_SERVER_TS_NAME = "event_origin_server_ts"
EVENT_FIELDS_SENDER_URL_UPDATE_NAME = "event_fields_sender_url"
DELETE_SOFT_FAILED_EXTREMITIES = "delete_soft_failed_extremities"
POPULATE_STREAM_ORDERING2 = "populate_stream_ordering2"
INDEX_STREAM_ORDERING2 = "index_stream_ordering2"
REPLACE_STREAM_ORDERING_COLUMN = "replace_stream_ordering_column"
@attr.s(slots=True, frozen=True)
class _CalculateChainCover:
"""Return value for _calculate_chain_cover_txn."""
@ -48,19 +67,15 @@ class _CalculateChainCover:
class EventsBackgroundUpdatesStore(SQLBaseStore):
EVENT_ORIGIN_SERVER_TS_NAME = "event_origin_server_ts"
EVENT_FIELDS_SENDER_URL_UPDATE_NAME = "event_fields_sender_url"
DELETE_SOFT_FAILED_EXTREMITIES = "delete_soft_failed_extremities"
def __init__(self, database: DatabasePool, db_conn, hs):
super().__init__(database, db_conn, hs)
self.db_pool.updates.register_background_update_handler(
self.EVENT_ORIGIN_SERVER_TS_NAME, self._background_reindex_origin_server_ts
_BackgroundUpdates.EVENT_ORIGIN_SERVER_TS_NAME,
self._background_reindex_origin_server_ts,
)
self.db_pool.updates.register_background_update_handler(
self.EVENT_FIELDS_SENDER_URL_UPDATE_NAME,
_BackgroundUpdates.EVENT_FIELDS_SENDER_URL_UPDATE_NAME,
self._background_reindex_fields_sender,
)
@ -85,7 +100,8 @@ class EventsBackgroundUpdatesStore(SQLBaseStore):
)
self.db_pool.updates.register_background_update_handler(
self.DELETE_SOFT_FAILED_EXTREMITIES, self._cleanup_extremities_bg_update
_BackgroundUpdates.DELETE_SOFT_FAILED_EXTREMITIES,
self._cleanup_extremities_bg_update,
)
self.db_pool.updates.register_background_update_handler(
@ -139,6 +155,24 @@ class EventsBackgroundUpdatesStore(SQLBaseStore):
self._purged_chain_cover_index,
)
# bg updates for replacing stream_ordering with a BIGINT
# (these only run on postgres.)
self.db_pool.updates.register_background_update_handler(
_BackgroundUpdates.POPULATE_STREAM_ORDERING2,
self._background_populate_stream_ordering2,
)
self.db_pool.updates.register_background_index_update(
_BackgroundUpdates.INDEX_STREAM_ORDERING2,
index_name="events_stream_ordering",
table="events",
columns=["stream_ordering2"],
unique=True,
)
self.db_pool.updates.register_background_update_handler(
_BackgroundUpdates.REPLACE_STREAM_ORDERING_COLUMN,
self._background_replace_stream_ordering_column,
)
async def _background_reindex_fields_sender(self, progress, batch_size):
target_min_stream_id = progress["target_min_stream_id_inclusive"]
max_stream_id = progress["max_stream_id_exclusive"]
@ -190,18 +224,18 @@ class EventsBackgroundUpdatesStore(SQLBaseStore):
}
self.db_pool.updates._background_update_progress_txn(
txn, self.EVENT_FIELDS_SENDER_URL_UPDATE_NAME, progress
txn, _BackgroundUpdates.EVENT_FIELDS_SENDER_URL_UPDATE_NAME, progress
)
return len(rows)
result = await self.db_pool.runInteraction(
self.EVENT_FIELDS_SENDER_URL_UPDATE_NAME, reindex_txn
_BackgroundUpdates.EVENT_FIELDS_SENDER_URL_UPDATE_NAME, reindex_txn
)
if not result:
await self.db_pool.updates._end_background_update(
self.EVENT_FIELDS_SENDER_URL_UPDATE_NAME
_BackgroundUpdates.EVENT_FIELDS_SENDER_URL_UPDATE_NAME
)
return result
@ -264,18 +298,18 @@ class EventsBackgroundUpdatesStore(SQLBaseStore):
}
self.db_pool.updates._background_update_progress_txn(
txn, self.EVENT_ORIGIN_SERVER_TS_NAME, progress
txn, _BackgroundUpdates.EVENT_ORIGIN_SERVER_TS_NAME, progress
)
return len(rows_to_update)
result = await self.db_pool.runInteraction(
self.EVENT_ORIGIN_SERVER_TS_NAME, reindex_search_txn
_BackgroundUpdates.EVENT_ORIGIN_SERVER_TS_NAME, reindex_search_txn
)
if not result:
await self.db_pool.updates._end_background_update(
self.EVENT_ORIGIN_SERVER_TS_NAME
_BackgroundUpdates.EVENT_ORIGIN_SERVER_TS_NAME
)
return result
@ -454,7 +488,7 @@ class EventsBackgroundUpdatesStore(SQLBaseStore):
if not num_handled:
await self.db_pool.updates._end_background_update(
self.DELETE_SOFT_FAILED_EXTREMITIES
_BackgroundUpdates.DELETE_SOFT_FAILED_EXTREMITIES
)
def _drop_table_txn(txn):
@ -1009,3 +1043,75 @@ class EventsBackgroundUpdatesStore(SQLBaseStore):
await self.db_pool.updates._end_background_update("purged_chain_cover")
return result
async def _background_populate_stream_ordering2(
self, progress: JsonDict, batch_size: int
) -> int:
"""Populate events.stream_ordering2, then replace stream_ordering
This is to deal with the fact that stream_ordering was initially created as a
32-bit integer field.
"""
batch_size = max(batch_size, 1)
def process(txn: Cursor) -> int:
# if this is the first pass, find the minimum stream ordering
last_stream = progress.get("last_stream")
if last_stream is None:
txn.execute(
"""
SELECT stream_ordering FROM events ORDER BY stream_ordering LIMIT 1
"""
)
rows = txn.fetchall()
if not rows:
return 0
last_stream = rows[0][0] - 1
txn.execute(
"""
UPDATE events SET stream_ordering2=stream_ordering
WHERE stream_ordering > ? AND stream_ordering <= ?
""",
(last_stream, last_stream + batch_size),
)
row_count = txn.rowcount
self.db_pool.updates._background_update_progress_txn(
txn,
_BackgroundUpdates.POPULATE_STREAM_ORDERING2,
{"last_stream": last_stream + batch_size},
)
return row_count
result = await self.db_pool.runInteraction(
"_background_populate_stream_ordering2", process
)
if result != 0:
return result
await self.db_pool.updates._end_background_update(
_BackgroundUpdates.POPULATE_STREAM_ORDERING2
)
return 0
async def _background_replace_stream_ordering_column(
self, progress: JsonDict, batch_size: int
) -> int:
"""Drop the old 'stream_ordering' column and rename 'stream_ordering2' into its place."""
def process(txn: Cursor) -> None:
for sql in _REPLACE_STREAM_ORDRING_SQL_COMMANDS:
logger.info("completing stream_ordering migration: %s", sql)
txn.execute(sql)
await self.db_pool.runInteraction(
"_background_replace_stream_ordering_column", process
)
await self.db_pool.updates._end_background_update(
_BackgroundUpdates.REPLACE_STREAM_ORDERING_COLUMN
)
return 0

View file

@ -12,7 +12,7 @@
# See the License for the specific language governing permissions and
# limitations under the License.
SCHEMA_VERSION = 59
SCHEMA_VERSION = 60
"""Represents the expectations made by the codebase about the database schema
This should be incremented whenever the codebase changes its requirements on the

View file

@ -0,0 +1,40 @@
/* Copyright 2021 The Matrix.org Foundation C.I.C
*
* 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.
*/
-- This migration handles the process of changing the type of `stream_ordering` to
-- a BIGINT.
--
-- Note that this is only a problem on postgres as sqlite only has one "integer" type
-- which can cope with values up to 2^63.
-- First add a new column to contain the bigger stream_ordering
ALTER TABLE events ADD COLUMN stream_ordering2 BIGINT;
-- Create a rule which will populate it for new rows.
CREATE OR REPLACE RULE "populate_stream_ordering2" AS
ON INSERT TO events
DO UPDATE events SET stream_ordering2=NEW.stream_ordering WHERE stream_ordering=NEW.stream_ordering;
-- Start a bg process to populate it for old events
INSERT INTO background_updates (ordering, update_name, progress_json) VALUES
(6001, 'populate_stream_ordering2', '{}');
-- ... and another to build an index on it
INSERT INTO background_updates (ordering, update_name, progress_json, depends_on) VALUES
(6001, 'index_stream_ordering2', '{}', 'populate_stream_ordering2');
-- ... and another to do the switcheroo
INSERT INTO background_updates (ordering, update_name, progress_json, depends_on) VALUES
(6001, 'replace_stream_ordering_column', '{}', 'index_stream_ordering2');