https://s3.amazonaws.com/clickhouse-test-reports/43986/7249ad407a0824d8c7651d8e03d4e68e1dea0813/stress_test__msan_.html
auto metadata_str = metadatas[file_path_prefix];
        UInt64 file_size = metadata_str.size();
        ReadBufferFromString buf(metadata_str);
        writeStringBinary(it.first, out);
        writeBinary(file_size, out);
        HashingWriteBuffer hashing_out(out);
        copyDataWithThrottler(buf, hashing_out, blocker.getCounter(), data.getSendsThrottler());
        if (blocker.isCancelled())
            throw Exception("Transferring part to replica was cancelled", ErrorCodes::ABORTED);
        if (hashing_out.count() != file_size)
            throw Exception(ErrorCodes::BAD_SIZE_OF_FILE_IN_DATA_PART, "Unexpected size of file {}", metadata_file_path);
        writePODBinary(hashing_out.getHash(), out);
    }
}
MergeTreeData::DataPartPtr Service::findPart(const String & name)
{
    
    
    auto part = data.getPartIfExists(
        name, {MergeTreeDataPartState::PreActive, MergeTreeDataPartState::Active, MergeTreeDataPartState::Outdated});
    if (part)
        return part;
    throw Exception(ErrorCodes::NO_SUCH_DATA_PART, "No part {} in table", name);
}
Fetcher::Fetcher(StorageReplicatedMergeTree & data_)
    : data(data_)
    , log(&Poco::Logger::get(data.getStorageID().getNameForLogs() + " (Fetcher)"))
{}
MergeTreeData::MutableDataPartPtr Fetcher::fetchSelectedPart(