public void updateAgentPidProperties(String startMode) {
		checkNotNull(home);
		Properties properties = home.getProperties("pid");
		Set<String> names = properties.stringPropertyNames();
		if (names.size() > 1) {
			properties.remove(startMode + ".pid");
			home.saveProperties("pid", properties);
		} else if (names.contains(startMode + ".pid")) {
			removeAgentPidProperties();
		}
	}
Update agent pid file.

@param startMode startMode
ngrinder-core/src/main/java/org/ngrinder/infra/AgentConfig.java