diff --git a/synapse/storage/client_ips.py b/synapse/storage/client_ips.py
index 9ad17b7c25..9c21362226 100644
--- a/synapse/storage/client_ips.py
+++ b/synapse/storage/client_ips.py
@@ -65,7 +65,32 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
columns=["last_seen"],
)
- # (user_id, access_token, ip) -> (user_agent, device_id, last_seen)
+ self.register_background_update_handler(
+ "user_ips_analyze",
+ self._analyze_user_ip,
+ )
+
+ self.register_background_update_handler(
+ "user_ips_remove_dupes",
+ self._remove_user_ip_dupes,
+ )
+
+ # Register a unique index
+ self.register_background_index_update(
+ "user_ips_device_unique_index",
+ index_name="user_ips_user_token_ip_unique_index",
+ table="user_ips",
+ columns=["user_id", "access_token", "ip"],
+ unique=True,
+ )
+
+ # Drop the old non-unique index
+ self.register_background_update_handler(
+ "user_ips_drop_nonunique_index",
+ self._remove_user_ip_nonunique,
+ )
+
+ # (user_id, access_token, ip,) -> (user_agent, device_id, last_seen)
self._batch_row_update = {}
self._client_ip_looper = self._clock.looping_call(
@@ -76,6 +101,205 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
)
@defer.inlineCallbacks
+ def _remove_user_ip_nonunique(self, progress, batch_size):
+ def f(conn):
+ txn = conn.cursor()
+ txn.execute(
+ "DROP INDEX IF EXISTS user_ips_user_ip"
+ )
+ txn.close()
+
+ yield self.runWithConnection(f)
+ yield self._end_background_update("user_ips_drop_nonunique_index")
+ defer.returnValue(1)
+
+ @defer.inlineCallbacks
+ def _analyze_user_ip(self, progress, batch_size):
+ # Background update to analyze user_ips table before we run the
+ # deduplication background update. The table may not have been analyzed
+ # for ages due to the table locks.
+ #
+ # This will lock out the naive upserts to user_ips while it happens, but
+ # the analyze should be quick (28GB table takes ~10s)
+ def user_ips_analyze(txn):
+ txn.execute("ANALYZE user_ips")
+
+ yield self.runInteraction(
+ "user_ips_analyze", user_ips_analyze
+ )
+
+ yield self._end_background_update("user_ips_analyze")
+
+ defer.returnValue(1)
+
+ @defer.inlineCallbacks
+ def _remove_user_ip_dupes(self, progress, batch_size):
+ # This works function works by scanning the user_ips table in batches
+ # based on `last_seen`. For each row in a batch it searches the rest of
+ # the table to see if there are any duplicates, if there are then they
+ # are removed and replaced with a suitable row.
+
+ # Fetch the start of the batch
+ begin_last_seen = progress.get("last_seen", 0)
+
+ def get_last_seen(txn):
+ txn.execute(
+ """
+ SELECT last_seen FROM user_ips
+ WHERE last_seen > ?
+ ORDER BY last_seen
+ LIMIT 1
+ OFFSET ?
+ """,
+ (begin_last_seen, batch_size)
+ )
+ row = txn.fetchone()
+ if row:
+ return row[0]
+ else:
+ return None
+
+ # Get a last seen that has roughly `batch_size` since `begin_last_seen`
+ end_last_seen = yield self.runInteraction(
+ "user_ips_dups_get_last_seen", get_last_seen
+ )
+
+ # If it returns None, then we're processing the last batch
+ last = end_last_seen is None
+
+ logger.info(
+ "Scanning for duplicate 'user_ips' rows in range: %s <= last_seen < %s",
+ begin_last_seen, end_last_seen,
+ )
+
+ def remove(txn):
+ # This works by looking at all entries in the given time span, and
+ # then for each (user_id, access_token, ip) tuple in that range
+ # checking for any duplicates in the rest of the table (via a join).
+ # It then only returns entries which have duplicates, and the max
+ # last_seen across all duplicates, which can the be used to delete
+ # all other duplicates.
+ # It is efficient due to the existence of (user_id, access_token,
+ # ip) and (last_seen) indices.
+
+ # Define the search space, which requires handling the last batch in
+ # a different way
+ if last:
+ clause = "? <= last_seen"
+ args = (begin_last_seen,)
+ else:
+ clause = "? <= last_seen AND last_seen < ?"
+ args = (begin_last_seen, end_last_seen)
+
+ # (Note: The DISTINCT in the inner query is important to ensure that
+ # the COUNT(*) is accurate, otherwise double counting may happen due
+ # to the join effectively being a cross product)
+ txn.execute(
+ """
+ SELECT user_id, access_token, ip,
+ MAX(device_id), MAX(user_agent), MAX(last_seen),
+ COUNT(*)
+ FROM (
+ SELECT DISTINCT user_id, access_token, ip
+ FROM user_ips
+ WHERE {}
+ ) c
+ INNER JOIN user_ips USING (user_id, access_token, ip)
+ GROUP BY user_id, access_token, ip
+ HAVING count(*) > 1
+ """.format(clause),
+ args
+ )
+ res = txn.fetchall()
+
+ # We've got some duplicates
+ for i in res:
+ user_id, access_token, ip, device_id, user_agent, last_seen, count = i
+
+ # We want to delete the duplicates so we end up with only a
+ # single row.
+ #
+ # The naive way of doing this would be just to delete all rows
+ # and reinsert a constructed row. However, if there are a lot of
+ # duplicate rows this can cause the table to grow a lot, which
+ # can be problematic in two ways:
+ # 1. If user_ips is already large then this can cause the
+ # table to rapidly grow, potentially filling the disk.
+ # 2. Reinserting a lot of rows can confuse the table
+ # statistics for postgres, causing it to not use the
+ # correct indices for the query above, resulting in a full
+ # table scan. This is incredibly slow for large tables and
+ # can kill database performance. (This seems to mainly
+ # happen for the last query where the clause is simply `? <
+ # last_seen`)
+ #
+ # So instead we want to delete all but *one* of the duplicate
+ # rows. That is hard to do reliably, so we cheat and do a two
+ # step process:
+ # 1. Delete all rows with a last_seen strictly less than the
+ # max last_seen. This hopefully results in deleting all but
+ # one row the majority of the time, but there may be
+ # duplicate last_seen
+ # 2. If multiple rows remain, we fall back to the naive method
+ # and simply delete all rows and reinsert.
+ #
+ # Note that this relies on no new duplicate rows being inserted,
+ # but if that is happening then this entire process is futile
+ # anyway.
+
+ # Do step 1:
+
+ txn.execute(
+ """
+ DELETE FROM user_ips
+ WHERE user_id = ? AND access_token = ? AND ip = ? AND last_seen < ?
+ """,
+ (user_id, access_token, ip, last_seen)
+ )
+ if txn.rowcount == count - 1:
+ # We deleted all but one of the duplicate rows, i.e. there
+ # is exactly one remaining and so there is nothing left to
+ # do.
+ continue
+ elif txn.rowcount >= count:
+ raise Exception(
+ "We deleted more duplicate rows from 'user_ips' than expected",
+ )
+
+ # The previous step didn't delete enough rows, so we fallback to
+ # step 2:
+
+ # Drop all the duplicates
+ txn.execute(
+ """
+ DELETE FROM user_ips
+ WHERE user_id = ? AND access_token = ? AND ip = ?
+ """,
+ (user_id, access_token, ip)
+ )
+
+ # Add in one to be the last_seen
+ txn.execute(
+ """
+ INSERT INTO user_ips
+ (user_id, access_token, ip, device_id, user_agent, last_seen)
+ VALUES (?, ?, ?, ?, ?, ?)
+ """,
+ (user_id, access_token, ip, device_id, user_agent, last_seen)
+ )
+
+ self._background_update_progress_txn(
+ txn, "user_ips_remove_dupes", {"last_seen": end_last_seen}
+ )
+
+ yield self.runInteraction("user_ips_dups_remove", remove)
+
+ if last:
+ yield self._end_background_update("user_ips_remove_dupes")
+
+ defer.returnValue(batch_size)
+
+ @defer.inlineCallbacks
def insert_client_ip(self, user_id, access_token, ip, user_agent, device_id,
now=None):
if not now:
@@ -114,7 +338,10 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
)
def _update_client_ips_batch_txn(self, txn, to_update):
- self.database_engine.lock_table(txn, "user_ips")
+ if "user_ips" in self._unsafe_to_upsert_tables or (
+ not self.database_engine.can_native_upsert
+ ):
+ self.database_engine.lock_table(txn, "user_ips")
for entry in iteritems(to_update):
(user_id, access_token, ip), (user_agent, device_id, last_seen) = entry
@@ -127,10 +354,10 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
"user_id": user_id,
"access_token": access_token,
"ip": ip,
- "user_agent": user_agent,
- "device_id": device_id,
},
values={
+ "user_agent": user_agent,
+ "device_id": device_id,
"last_seen": last_seen,
},
lock=False,
@@ -227,7 +454,7 @@ class ClientIpStore(background_updates.BackgroundUpdateStore):
results = {}
for key in self._batch_row_update:
- uid, access_token, ip = key
+ uid, access_token, ip, = key
if uid == user_id:
user_agent, _, last_seen = self._batch_row_update[key]
results[(access_token, ip)] = (user_agent, last_seen)
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