Merge pull request #886 from matrix-org/markjh/async_commit

Optionally make committing to postgres asynchronous.
This commit is contained in:
Mark Haines 2016-06-29 15:21:58 +01:00 committed by GitHub
commit 6783534a0f
3 changed files with 14 additions and 3 deletions

View File

@ -32,7 +32,7 @@ def create_engine(database_config):
if engine_class:
module = importlib.import_module(name)
return engine_class(module)
return engine_class(module, database_config)
raise RuntimeError(
"Unsupported database engine '%s'" % (name,)

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@ -19,9 +19,10 @@ from ._base import IncorrectDatabaseSetup
class PostgresEngine(object):
single_threaded = False
def __init__(self, database_module):
def __init__(self, database_module, database_config):
self.module = database_module
self.module.extensions.register_type(self.module.extensions.UNICODE)
self.synchronous_commit = database_config.get("synchronous_commit", True)
def check_database(self, txn):
txn.execute("SHOW SERVER_ENCODING")
@ -40,9 +41,19 @@ class PostgresEngine(object):
db_conn.set_isolation_level(
self.module.extensions.ISOLATION_LEVEL_REPEATABLE_READ
)
# Asynchronous commit, don't wait for the server to call fsync before
# ending the transaction.
# https://www.postgresql.org/docs/current/static/wal-async-commit.html
if not self.synchronous_commit:
cursor = db_conn.cursor()
cursor.execute("SET synchronous_commit TO OFF")
cursor.close()
def is_deadlock(self, error):
if isinstance(error, self.module.DatabaseError):
# https://www.postgresql.org/docs/current/static/errcodes-appendix.html
# "40001" serialization_failure
# "40P01" deadlock_detected
return error.pgcode in ["40001", "40P01"]
return False

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@ -21,7 +21,7 @@ import struct
class Sqlite3Engine(object):
single_threaded = True
def __init__(self, database_module):
def __init__(self, database_module, database_config):
self.module = database_module
def check_database(self, txn):