static long getPidJiffies(VespaService service) {
        int pid = service.getPid();
        try {
            BufferedReader in = new BufferedReader(new FileReader("/proc/" + pid + "/stat"));
            return getPidJiffies(in);
        } catch (FileNotFoundException ex) {
            log.log(Level.FINE, () -> "Unable to find pid " + pid + " in proc directory, for service " + service.getInstanceName());
            service.setAlive(false);
            return 0;
        }
    }
@Test
    public void testPerProcessJiffies() {
        assertEquals(PER_PROC_JIFFIES[0], SystemPoller.getPidJiffies(new BufferedReader(new StringReader(perProcStats[0]))));
        assertEquals(PER_PROC_JIFFIES[1], SystemPoller.getPidJiffies(new BufferedReader(new StringReader(perProcStats[1]))));
    }