Add the missing index on the peewee side. We already have the associated migration.

data/database.py

@@ -561,6 +561,14 @@ class LogEntry(BaseModel):
   ip = CharField(null=True)
   metadata_json = TextField(default='{}')
 
+  class Meta:
+    database = db
+    read_slaves = (read_slave,)
+    indexes = (
+      # create an index on repository and date
+      (('repository', 'datetime'), False),
+    )
+
 
 class RepositoryActionCount(BaseModel):
   repository = ForeignKeyField(Repository, index=True)