private static String[] stripForkedArgs(String[] args) {
        List<String> ret = new ArrayList<>();
        for (String arg : args) {
            if (!arg.startsWith("-J")) {
                ret.add(arg);
            }
        }
        return ret.toArray(new String[0]);
    }
This value is set to the server's id in the forked process.
tika-server/tika-server-core/src/main/java/org/apache/tika/server/core/TikaServerCli.java