mainClassName LinuxProcessSizeDetector

set flag Reparse.
set flag LeanMode.
set flag l_withoutReflection.
set flag NoAutoGunzip.
do not include function get.

sbool linux_rssFixedForZGC_verbose;

public static long linux_rssFixedForZGC() throws IOException {
  ret linux_rssFixedForZGC(processID_int());
}

public static long linux_rssFixedForZGC(int pid) throws IOException {
  //if (!is64BitLinux()) fail("Not on 64 Bit Linux");
  
  S range = null;
  new TreeMap<S, Long> rssByRange;
  Pattern patAddr = Pattern.compile("^([0-9a-f]{1,16})-");
  temp BufferedReader in = new BufferedReader(new InputStreamReader(new FileInputStream("/proc/" + pid + "/smaps")));
  S s;
  while ((s = in.readLine()) != null) {
    Matcher m = patAddr.matcher(s);
    S addr = m.find() ? m.group(1) : null;
    if (addr != null) {
      //print("Have address: " + addr);
      S cleanedAddr = longToHex(parseUnsignedHexLong(addr) & ~((1L << 42)-1));
      range = takeFirst_string(6, cleanedAddr);
      continue;
    } // else print("Not range: " + s);
    S[] p = parseColonProperty_array(s);
    if (eqic(first(p), "rss")) {
      long size = Long.parseLong(beforeSpace(p[1]));
      if (size != 0)
        rssByRange.put(range, getOrCreate_long(rssByRange, range) + size);
    }
  }
  if (linux_rssFixedForZGC_verbose)
    for (Map.Entry<S, Long> e : rssByRange.entrySet()) {
      System.out.println("Address range " + rpad(e.getKey(), 16, 'x') + ": " + toK(e.getValue()) + " MB");
    }
    
  Long min = null;
  for (S _range : ll("000004", "000008", "000010", "00007c")) {
    Long l = rssByRange.get(_range);
    if (l != null) min = min == null ? l : Math.min(min, l);
  }

  long total = 0;
  for (long l : rssByRange.values()) total += l;
  long guess = min == null ? total : total-min*3;
  ret guess*1024;
}

Began life as a copy of #1025548