Tweaking SAP Netweaver 7.01 ABAP on VM

The SAP system now needs to be tweaked.  This is to allow it to run comfortably in a VM with limited resources.  My setup is limited by the host machine which runs 32-bit Windows 7.  32-bit Windows have access to only 3GB of RAM or slightly more, and that is if the hardware allows it.  This is so, even if the machine has 4GB of RAM.

I have initially assigned 1.5GB of RAM to the VM, but there seems to be quite a bit of disk thrashing.

Tweaking the OS
This is when I started googling to see if anything can help my poor harddisk.
1. Stop NTFS from updating the access timestamp on the filesystem.  This is done by adding an entry to the registry.  Using regedit, add to HKLM\SYSTEM\CurrentControlSet\FileSystem an entry NtfsDisableLastAccessUpdate (DWORD value of 1).

2. Turn off System Restore through Control Panel , System, System Restore

According the SAP Help, in the section on SAP Memory Management (BC-CST-MM), it states that 'Windows file cache directly competes with SAP programs for physical memory by pushing them out of the memory.'  Hence, following the instructions there, set System Properties  → Advanced  → Performance → Settings → choose Advanced → Processor Scheduling → Background services.  For Memory Usage → Programs

I decided to then install Process Explorer, a really fantastic system tool.  Guess what, the memory usage is at 2.5GB, way above the 1.5GB I have given to my VM, and above the 1GB minimum stated in SAP's minimum requirements.  I suppose that is for a physical machine where swapping is acceptable.

Next up, we'll see if SAP's parameters can be tweaked to reduce its memory consumption.

Tweaking the Database

Move database files to a fixed preallocated virtual disk.

Create a new preallocated vmdk file.  Then add to the OS using Administrative Tools; Computer Management; Disk Management.

Then using the Database Manager, move the volumes and log to the new drive using the instructions here.  Essentially, bring database offline, do a OS file copy to the new drive, point the volumes there, and finally bring database back online.  I am missing the dbmrelocate executable which would have made it easier.  This allows me to move the C:\sapdb\NSP\sapdata and C:\sapdb\NSP\saplog, but cannot find how to move C:\sapdb\NSP\db.  Well, that may suffice for now. 

All these work is not sufficient to stop the thrashing.  Watch this space for updates.