buf.append("\"process\":{");
        final ProcessProbe processProbe = ProcessProbe.getInstance();
        buf.append("\"file_descriptor\":{");
        append(buf, "open", () -> processProbe.getOpenFileDescriptorCount()).append(',');
        append(buf, "max", () -> processProbe.getMaxFileDescriptorCount());
        buf.append("},");
        buf.append("\"cpu\":{");