```
ubuntu@ip-172-31-79-147:/opt/downloads$ clickhouse-local --max_threads 8 --query "WITH parseDateTimeBestEffort(extract(_path, 'pageviews-([\\d\\-]+)\\.gz$')) AS time, splitByChar(' ', line) AS values, splitByChar('.', values[1]) AS projects SELECT time, projects[1] AS project, projects[2] AS subproject, values[2] AS path, (values[3])::UInt64 AS hits FROM file('pageviews*.gz', LineAsString) WHERE length(values) >= 3" | pv > /dev/null
^C01GiB 0:01:08 [ 129MiB/s] [                                                                                                                                                                   <=>                                                                                    ]

ubuntu@ip-172-31-79-147:/opt/downloads$ clickhouse-local --max_threads 8 --query "WITH parseDateTimeBestEffort(extract(toLowCardinality(_path), 'pageviews-([\\d\\-]+)\\.gz$')) AS time, splitByChar(' ', line) AS values, splitByChar('.', values[1]) AS projects SELECT time, projects[1] AS project, projects[2] AS subproject, values[2] AS path, (values[3])::UInt64 AS hits FROM file('pageviews*.gz', LineAsString) WHERE length(values) >= 3" | pv > /dev/null
^C46GiB 0:00:48 [ 175MiB/s] [                                                                                                                                                                                                                                        <=>               ]
```

{
    size_t batch_size = kafka_settings->kafka_poll_max_batch_size.changed
                        ? kafka_settings->kafka_poll_max_batch_size.value
                        : getContext()->getSettingsRef().max_block_size.value;
    return std::min(batch_size,getMaxBlockSize());
}
size_t StorageKafka::getPollTimeoutMillisecond() const
{
    return kafka_settings->kafka_poll_timeout_ms.changed
        ? kafka_settings->kafka_poll_timeout_ms.totalMilliseconds()
        : getContext()->getSettingsRef().stream_poll_timeout_ms.totalMilliseconds();
}
String StorageKafka::getConfigPrefix() const
{
    if (!collection_name.empty())
        return "named_collections." + collection_name + "." + CONFIG_PREFIX; 
    return CONFIG_PREFIX;
}
void StorageKafka::updateConfiguration(cppkafka::Configuration & conf)
{
    
    const auto & config = getContext()->getConfigRef();
    auto config_prefix = getConfigPrefix();
    if (config.has(config_prefix))
        loadFromConfig(conf, config, config_prefix);
    
    for (const auto & topic : topics)
    {