final long freeBytes = runtime.freeMemory();
        final long maxBytes = runtime.maxMemory();
        final long totalBytes = runtime.totalMemory();
        final long usedBytes = totalBytes - freeBytes;
        return "Mem:{used " + byteCountToDisplaySize(usedBytes) + ", heap " + byteCountToDisplaySize(totalBytes) + ", max "
                + byteCountToDisplaySize(maxBytes) + "}";
    }

    /**