And waits for them. That's pointless.
{
    size_t num_tries = 0;
    bool success = false;
    while (!success && (max_retries == 0 || num_tries < max_retries))
    {
        try
        {
            ++num_tries;
            success = true;
            auto zookeeper = getZooKeeper();
            std::vector<std::future<Coordination::ExistsResponse>> exists_futures;
            exists_futures.reserve(part_names.size());
            for (const String & part_name : part_names)
            {
                String part_path = fs::path(replica_path) / "parts" / part_name;
                exists_futures.emplace_back(zookeeper->asyncExists(part_path));
            }
            std::vector<std::future<Coordination::MultiResponse>> remove_futures;
            remove_futures.reserve(part_names.size());
            for (size_t i = 0; i < part_names.size(); ++i)
            {
                Coordination::ExistsResponse exists_resp = exists_futures[i].get();
                if (exists_resp.error == Coordination::Error::ZOK)
                {
                    Coordination::Requests ops;
                    removePartFromZooKeeper(part_names[i], ops, exists_resp.stat.numChildren > 0);
                    remove_futures.emplace_back(zookeeper->asyncTryMultiNoThrow(ops));
                }