Deactivate sk timelines when no compute activity

[petuhovskiy]

In-memory timelines will be deactivated after there will be no compute connections for more than 10 minutes. Deactivation here will set active = false in SharedState struct and that will stop pushing info about this timeline to etcd.

Timeline deactivation happens in update_status, which is called on every etcd message from the peer.

[petuhovskiy]

Tested locally with a test that counts active timelines:

from fixtures.metrics import parse_metrics

def test_plenty_timelines(neon_env_builder: NeonEnvBuilder):
    neon_env_builder.num_safekeepers = 3
    neon_env_builder.enable_local_fs_remote_storage()
    env = neon_env_builder.init_start()

    # start postgres on each timeline
    pgs = []
    branch_idx = 0

    def create_branch():
        nonlocal branch_idx
        branch_name = f"abc_{branch_idx}"
        branch_idx += 1
        new_timeline_id = env.neon_cli.create_branch(branch_name)
        pg = env.postgres.create_start(branch_name)
        pg.safe_psql("CREATE TABLE IF NOT EXISTS t (key INT)")
        pg.safe_psql(f"INSERT INTO t (key) VALUES ({branch_idx})")
        pg.stop()
        pgs.append(pg)

    def report_metrics():
        # collect metrics from other servers
        for sk in env.safekeepers:
            all_metrics = parse_metrics(sk.http_client().get_metrics_str())
            active_tlis = sum(map(lambda f: int(f.value), all_metrics.query_all("safekeeper_timeline_active", {})))

            log.info(f"Safekeeper {sk.id} have {active_tlis} active timelines")

    for i in range(100):
        create_branch()

    report_metrics()

    # sleep until timelines are deactivated
    time.sleep(50)

    for j in range(10):
        for i in range(10):
            create_branch()

        report_metrics()
        time.sleep(10)

[arssher]

Superseded by 26746