Max Tasks and MTServers

Hello experts,

Currently we are using a enterprise with 4 siebel application servers each is having eCommunicationsObjMgr_enu 20 MTServers and 400 Max tasks. But when checked most of the eCommunicationsObjMgr_enu processes are hitting above 1400 MB size. So can we change

the MTServers to 40? What would be the impact? Can we change the MTServers parameter on only one server for testing purpose?

Below is the output of prstat -a from one of the servers. Most of the below processes are of  eCommunicationsObjMgr_enu.

  PID USERNAME  SIZE   RSS STATE  PRI NICE      TIME  CPU PROCESS/NLWP

24079 siebel    893M  768M sleep   59    0   3:51:08 0.4% siebmtshmw/36

23006 siebel    828M  703M sleep   59    0   1:11:29 0.4% siebmtshmw/36