Increase Windows Heap Size to address MMD crashes

  • KM02866330
  • 19-Jul-2017
  • 19-Jul-2017


Increase Windows Heap Size to address MMD crashes in Windows Cell Managers


MMD crashes may be the underlying cause to errors such as

[Critical] From: BSM@CM_Host "xxx_DB_LOGS" Time: 5/23/2017 3:00:44 PM

Could not establish connection with MMD within 60 minutes.

Session will be aborted.


Check Windows Event logs for MMD crashes at that time.


For the Windows box hosting the MMD (mom) increase the desktop heap via registry setting:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\SubSystems\Windows

Default value is:

%SystemRoot%\system32\csrss.exe ObjectDirectory=\Windows SharedSection=1024,20480,768 Windows=On SubSystemType=Windows ServerDll=basesrv,1 ServerDll=winsrv:UserServerDllInitialization,3 ServerDll=winsrv:ConServerDllInitialization,2 ServerDll=sxssrv,4 ProfileControl=Off MaxRequestThreads=16

change this SharedSection part:
SharedSection=1024,20480,768 -> SharedSection=1024,20480,10240

It’s a performance tuning recommendation for high IO operations such as MMD process on MOM.

For details, see the following: