Saving PCD files consumes memory after writing the file

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Your Environment

• Operating System and version: Jetson TX1 Ubuntu 16.04
• Compiler: 5.4.0
• PCL Version: 1.8 (from git)

Current Behavior

Using pcl::io::savePCDFile() consumes as much RAM as the filesize. As I am running this in a loop, this quickly consumes all memory until the program crashes. The memory is freed when I delete the files from disk while the program is running, and some of it is freed when I terminate the program. This occurs with all methods of saving PCD files.

Expected Behavior

Saving PCD files to disk should not consume all the RAM even after the file has been written

Code to Reproduce

    int savePersonCluster(PointCloud::ConstPtr cloud, pcl::people::PersonCluster<PointT> cluster, std::string uuid) {
        PointCloud::Ptr tmp(new PointCloud);
        pcl::CropBox<PointT> crop;
        crop.setInputCloud(cloud);
        crop.setMin(Eigen::Vector4f(cluster.getMin().x(), cluster.getMin().y(), cluster.getMin().z(), 0));
        crop.setMax(Eigen::Vector4f(cluster.getMax().x(), cluster.getMax().y(), cluster.getMax().z(), 0));
        crop.filter(*tmp);
        tmp->header.frame_id = cloud->header.frame_id;
        std::stringstream ss;
        ss << cluster_save_path << "/" << uuid << std::string(".pcd");
        if (save_person_clusters) pcl::io::savePCDFileBinaryCompressed(ss.str(), *tmp);
        return tmp->points.size();
    }

Setting save_person_clusters to false does not consume any memory.

Context

I am pulling pointclouds from a Kinect v2 using iai_kinect2 using ROS.

Start at pcl::io::savePCDFileBinaryCompressed, then reproduce the reported loop on the Jetson TX1 environment using the provided savePersonCluster example. Trace memory ownership during repeated PCD writes and verify that repeated saves no longer accumulate RAM; add or run a regression test if the relevant test location is identified.