kafka consumer takes very, very long time to start

Question

Defaults must be bad or something is very wrong.

I run produce and consumer in separate REPL.

import datetime
import uuid
import time
import json

import msgpack

from kafka import KafkaProducer, KafkaConsumer
from kafka.errors import KafkaError

topic = 'my-topic'
def get_consumer():
    return KafkaConsumer(topic,
            # client_id=str(uuid.uuid1()),
            fetch_max_wait_ms=1,
            group_id='my-group',
            metadata_max_age_ms=10,
            bootstrap_servers=['localhost:9092'],
            value_deserializer=msgpack.loads)

consumer = get_consumer()

producer = KafkaProducer(
        bootstrap_servers=["localhost:9092"],
        value_serializer=msgpack.dumps)

def produce_n(n=100):
    for i in range(n):
        print(i)
        producer.send(topic, value=time.time())
        time.sleep(1)
        producer.flush()

def consume():
    consumer = get_consumer()
    for x in consumer:
        T = time.time()
        dt = T - x.value
        print(x)
        print(f't={x.value} T={T} dt={dt} ms')