1 Reply Latest reply: May 11, 2013 2:08 AM by 819458 RSS

    OPMN CPU Usage

    819458
      we've noticed very high cpu usage by the opmn process when a relatively large number of forms users (several hundred) are connected

      Running a truss on the opmn process show's it to be interrogating the /proc filesystem for all the frmweb processes - pretty much constantly e.g.

      4934/16: open("/proc/23356/xmap", O_RDONLY) = 14
      4934/16: fcntl(14, F_SETFD, 0x00000001) = 0
      4934/16: fstat(14, 0xFFFFFFFF77BFAE58) = 0
      4934/16: pread(14, "\0\0\001\0\0\0\0\0\0\0\0".., 28944, 0) = 28944
      4934/16: pread(14, "\0\0\001\0\0\0\0\0\0\0\0".., 43416, 0) = 43416
      4934/16: pread(14, "\0\0\001\0\0\0\0\0\0\0\0".., 57888, 0) = 57888
      4934/16: pread(14, "\0\0\001\0\0\0\0\0\0\0\0".., 72360, 0) = 72360
      4934/16: pread(14, "\0\0\001\0\0\0\0\0\0\0\0".., 86832, 0) = 85968
      4934/16: close(14) = 0
      4934/16: open("/proc/23356/psinfo", O_RDONLY) = 14
      4934/16: fcntl(14, F_SETFD, 0x00000001) = 0
      4934/16: read(14, "02\0\0\0\0\0\001\0\0 [ <".., 416)     = 416
      4934/16: close(14) = 0
      4934/16: open("/proc/23356/usage", O_RDONLY) = 14
      4934/16: fcntl(14, F_SETFD, 0x00000001) = 0
      4934/16: read(14, "\0\0\0\0\0\0\001\0\0\0\0".., 504) = 504
      4934/16: close(14) = 0
      4934/16: open("/proc/23356/status", O_RDONLY) = 14
      4934/16: fcntl(14, F_SETFD, 0x00000001) = 0
      4934/16: read(14, "\t\0 @ 0\0\0\001\0\0 [ <".., 1776)    = 1776
      4934/16: close(14) = 0

      pid 23356 is an frmweb process

      oracle 23356 5367 0 12:03:04 pts/5 0:23 frmweb webfile=HTTP-0

      and the cycle just repeats for all the forms web processes

      clearly this isn't very scalable - the more forms processes the harder opmn has to work to scan them all

      does anyone know why opmn is doing this - and if there's a way to stop it ?

      this is on solaris 10 and Weblogic 10.3.5.0 + Oracle Forms/Reports Services 11.1.2.0

      cheers
      steve
        • 1. Re: OPMN CPU Usage
          819458
          at the risk of answering my own question, have discovered that if you remove the section

          <ias-component id="forms" type="FormsComponent">
          <process-type id="FormsRuntime" status="phantom">
          </process-type>
          </ias-component>

          from the opmn.xml file in$MW_HOME/asinst_1/config/OPMN/opmn and reload e.g.

          $ORACLE_HOME/opmn/bin/opmnctl reload

          then opmn stops monitoring the forms runtimes and cpu usage drops back to a sensible level

          also then doing

          $ORACLE_HOME/opmn/bin/opmnctl status

          no longer lists all the forms runtime processes and the 11gAS web console is more responsive

          cant find any documentation on this anywhere so usual caveats apply - it may break your production system, steal your dog or eat your lunch so be careful