Simple tomcat memory monitoring

1. Write a java class/jsp
 
Runtime run = Runtime. getRuntime ();
 
Long max = run. maxMemory ()/1024/1024; // maximum memory
 
Long total = run. totalMemory ()/1024/1024; // allocated memory
Long free = run. freeMemory ()/1024/1024; // available space
 
If (run. freeMemory ()/1024/1024) <150 ){
 
JavaMailSenderImpl sender = new JavaMailSenderImpl ();
 
Sender. setHost ("192.168.1.1 ");
 
MimeMessage message = sender. createMimeMessage ();
 
MimeMessageHelper helper = new MimeMessageHelper (message, true,
 
UTF-8 ");
 
Helper. setFrom ("miotourerror@mic.com.tw ");
 
Helper. setTo (new String [] {"itxinmeng@gmail.com "});
 
Helper. setSubject ("miotour exception ");
 
String content = "mio tour is at the edge of downtime, with only the memory left:" + free + "M ";
 
Content = content + "<br> ";
 
Helper. setText (content, true );
 
Sender. send (message );
 
}
 
2. Add timing in linux (under fedora 11 ):
 
/Etc/crontab-e Add the following content (query every 15 minutes)
 
*/15 * curl http://www.aaa.com/memory-detail.jsp
 
/Sbin/service crond restart

Author Hill