Optionally make committing to postgres asynchronous.

Useful when running tests when you don't care whether the server
will lose data that it claims that it has committed.
This commit is contained in:
Mark Haines 2016-06-20 17:53:38 +01:00
parent 9ba2bf1570
commit d5fb561709
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,)

View file

@ -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

View file

@ -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):