That is why my Tomcats spawn a pool of sh scripts to have them run a unix command (ImageMagick, etc.) Forking of a threaded process is very expensive on a loaded server. Unix has to suspend all threads, than fork, do a lot of housekeeping and than resume all threads. After making a pool of running sh instances which listen on stdin for commands my system %cpu went down so it has more time for user %cpu. Throughput doubled in my scenario's.
Ronald. Op woensdag, 17 november 2010 22:30 schreef Leon Rosenberg <rosenberg.l...@gmail.com>:
Hi,I have a ugly issue I'm sure many people on this list already solved. For multiple purposes I need pid's of processes, to stop/start them or ensure they are running. So far nothing spectacular. To obtain the pid I have following util: String[] cmd = { "/bin/bash", "-c", "echo $PPID" }; p = Runtime.getRuntime().exec(cmd); and afterwards read the ppid from the output stream of my process. So far - so good. The problem now occurs if a process has a lot of memory configured. Like 25Gb on a 32Gb machine. In such a configuration the above command fails with an OS'es out of memory, because fork fails to create another process with THAT amount of memory: 1598388 2010-11-17 02:54:47,061 ERROR net.anotheria.util.PidTools - Could not determine PID: java.io.IOException: Cannot run program "/bin/bash": java.io.IOException: error=12, Cannot allocate memory Is there another method to obtain the process id from within the process? regards Leon --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
