1 Reply Latest reply on Feb 4, 2008 10:38 AM by Peter Johnson

    help me understand memory usage

    Dave Chen Master

      On Linux FC 6. The machine physical memory is 4G.

      After machine reboot, start JBoss and deploy application, the total memory usage is about 700M. After running JBoss for several hours, the memory used is increased to 3.5G.

      $ ps -eo rss

      Adding all used memory up, the total is about 580M. where does the rest memory go?

      $ top
      Tasks: 95 total, 2 running, 93 sleeping, 0 stopped, 0 zombie
      Cpu(s): 0.0%us, 0.1%sy, 0.0%ni, 99.7%id, 0.0%wa, 0.2%hi, 0.0%si, 0.0%st
      Mem: 4037992k total, 3456532k used, 581460k free, 626264k buffers
      Swap: 10223608k total, 0k used, 10223608k free, 2119340k cached

      PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
      12529 root 25 0 2502m 388m 43m S 0 9.9 1:27.33 java
      2584 root 15 0 326m 114m 3596 S 0 2.9 1491:46 yum-updatesd
      2404 mysql 15 0 246m 26m 4236 S 0 0.7 1:28.03 mysqld

      the JBoss (java): 388M.

      Please help me.
      Thanks
      Dave