Files
neon/test_runner/batch_others/test_branch_behind.py
Dmitry Rodionov 5d490babf8 add node id to pageserver
This adds node id parameter to pageserver configuration. Also I use a
simple builder to construct pageserver config struct to avoid setting
node id to some temporary invalid value. Some of the changes in test
fixtures are needed to split init and start operations for envrionment.
2022-02-23 08:33:50 +03:00

137 lines
5.1 KiB
Python

import subprocess
from contextlib import closing
import psycopg2.extras
import pytest
from fixtures.log_helper import log
from fixtures.utils import print_gc_result
from fixtures.zenith_fixtures import ZenithEnvBuilder
#
# Create a couple of branches off the main branch, at a historical point in time.
#
def test_branch_behind(zenith_env_builder: ZenithEnvBuilder):
# Use safekeeper in this test to avoid a subtle race condition.
# Without safekeeper, walreceiver reconnection can stuck
# because of IO deadlock.
#
# See https://github.com/zenithdb/zenith/issues/1068
zenith_env_builder.num_safekeepers = 1
env = zenith_env_builder.init_start()
# Branch at the point where only 100 rows were inserted
env.zenith_cli.create_branch("test_branch_behind", "main")
pgmain = env.postgres.create_start('test_branch_behind')
log.info("postgres is running on 'test_branch_behind' branch")
main_pg_conn = pgmain.connect()
main_cur = main_pg_conn.cursor()
main_cur.execute("SHOW zenith.zenith_timeline")
timeline = main_cur.fetchone()[0]
# Create table, and insert the first 100 rows
main_cur.execute('CREATE TABLE foo (t text)')
# keep some early lsn to test branch creation on out of date lsn
main_cur.execute('SELECT pg_current_wal_insert_lsn()')
gced_lsn = main_cur.fetchone()[0]
main_cur.execute('''
INSERT INTO foo
SELECT 'long string to consume some space' || g
FROM generate_series(1, 100) g
''')
main_cur.execute('SELECT pg_current_wal_insert_lsn()')
lsn_a = main_cur.fetchone()[0]
log.info(f'LSN after 100 rows: {lsn_a}')
# Insert some more rows. (This generates enough WAL to fill a few segments.)
main_cur.execute('''
INSERT INTO foo
SELECT 'long string to consume some space' || g
FROM generate_series(1, 200000) g
''')
main_cur.execute('SELECT pg_current_wal_insert_lsn()')
lsn_b = main_cur.fetchone()[0]
log.info(f'LSN after 200100 rows: {lsn_b}')
# Branch at the point where only 100 rows were inserted
env.zenith_cli.create_branch("test_branch_behind_hundred", "test_branch_behind@" + lsn_a)
# Insert many more rows. This generates enough WAL to fill a few segments.
main_cur.execute('''
INSERT INTO foo
SELECT 'long string to consume some space' || g
FROM generate_series(1, 200000) g
''')
main_cur.execute('SELECT pg_current_wal_insert_lsn()')
main_cur.execute('SELECT pg_current_wal_insert_lsn()')
lsn_c = main_cur.fetchone()[0]
log.info(f'LSN after 400100 rows: {lsn_c}')
# Branch at the point where only 200100 rows were inserted
env.zenith_cli.create_branch("test_branch_behind_more", "test_branch_behind@" + lsn_b)
pg_hundred = env.postgres.create_start("test_branch_behind_hundred")
pg_more = env.postgres.create_start("test_branch_behind_more")
# On the 'hundred' branch, we should see only 100 rows
hundred_pg_conn = pg_hundred.connect()
hundred_cur = hundred_pg_conn.cursor()
hundred_cur.execute('SELECT count(*) FROM foo')
assert hundred_cur.fetchone() == (100, )
# On the 'more' branch, we should see 100200 rows
more_pg_conn = pg_more.connect()
more_cur = more_pg_conn.cursor()
more_cur.execute('SELECT count(*) FROM foo')
assert more_cur.fetchone() == (200100, )
# All the rows are visible on the main branch
main_cur.execute('SELECT count(*) FROM foo')
assert main_cur.fetchone() == (400100, )
# Check bad lsn's for branching
# branch at segment boundary
env.zenith_cli.create_branch("test_branch_segment_boundary", "test_branch_behind@0/3000000")
pg = env.postgres.create_start("test_branch_segment_boundary")
cur = pg.connect().cursor()
cur.execute('SELECT 1')
assert cur.fetchone() == (1, )
# branch at pre-initdb lsn
with pytest.raises(Exception, match="invalid branch start lsn"):
env.zenith_cli.create_branch("test_branch_preinitdb", "main@0/42")
# branch at pre-ancestor lsn
with pytest.raises(Exception, match="less than timeline ancestor lsn"):
env.zenith_cli.create_branch("test_branch_preinitdb", "test_branch_behind@0/42")
# check that we cannot create branch based on garbage collected data
with closing(env.pageserver.connect()) as psconn:
with psconn.cursor(cursor_factory=psycopg2.extras.DictCursor) as pscur:
# call gc to advace latest_gc_cutoff_lsn
pscur.execute(f"do_gc {env.initial_tenant.hex} {timeline} 0")
row = pscur.fetchone()
print_gc_result(row)
with pytest.raises(Exception, match="invalid branch start lsn"):
# this gced_lsn is pretty random, so if gc is disabled this woudln't fail
env.zenith_cli.create_branch("test_branch_create_fail", f"test_branch_behind@{gced_lsn}")
# check that after gc everything is still there
hundred_cur.execute('SELECT count(*) FROM foo')
assert hundred_cur.fetchone() == (100, )
more_cur.execute('SELECT count(*) FROM foo')
assert more_cur.fetchone() == (200100, )
main_cur.execute('SELECT count(*) FROM foo')
assert main_cur.fetchone() == (400100, )