Notes on using SMP on the Merlin Convenience Pack


New readers should see the warning at the end of this page.

This is a summary of experiences and information about using Symmetrical Multiprocessing (SMP) on the Merlin Convenience Pack (MCP); it may also apply on later fix levels of Warp 4 (e.g. FixPack 15).

Note that the files required to do this need to be taken from a system running Warp Server for e-Business (WSeB) or from an SMP version of eComStation (eCS). If these files are used on another system, an additional license for the 'donating' system must be held.

Conversion procedure

Three files must be replaced for the conversion; these are:

Note that these are all 'special' versions, and if you are copying them from a uniprocessor system they will not be in the expected places. You should, however, find them in the directory \OS2\INSTALL\SMP.

It is suggested that, to avoid confusion, you store copies of these files in the directory \OS2\INSTALL\SMP on the system that you are 'converting'. For safety, also copy your existing versions of these files to \OS2\INSTALL\UNI. You will probably find that these directories already exist, in any case.

You will not be able to update DOSCALL1.DLL on a running system; it is also probably not wise to use a utility that updates DLLs 'on the fly' in this case. So, boot to a maintenance command prompt, copy over these three files and reboot. That's it! If you need to reverse the process, just replace the files from \OS2\INSTALL\UNI.

One file must also be added, a .PSD file. Usually, this will be OS2APIC.PSD, which is found in \OS2\BOOT; there are other platform specific PSD files in the same place. You will need to put the line:


into CONFIG.SYS. It doesn't really matter where it goes.

What you will see

Well, your system should run faster! This is not quantifiable and will depend on the programs you run, what you run alongside what, and so on.

On the WarpCenter, you should see two coloured lines instead of one; each shows the load on one of the CPUs.


You may find that a later version of the kernel is beneficial; start by looking at


These utilities will be found useful; they are probably already on your MCP system:

A simple CPU monitor program. Run it and select the HELP menu item for more information.
A program for marking executable programs so that they only run on one CPU. This is useful if the program cannot correctly cope with the SMP environment. Run the program without any parameters to see usage notes.

Known problems

There is a problem when using Peer networking. This causes a Trap E in NETWKSTA.200, usually at Peer shutdown. The fix, IC31990, comes in two flavours depending on the version and fix level of Peer that is in use. Start by reading the file; the two zip files mentioned can be found in the same directory.


The information herein is provided without guarantee or warranty. Users should be aware that some of the procedures detailed here may not work for them, and may result in loss of data. Backups of critical data should be taken before attempting to use these procedures.

The information herein is not endorsed by IBM in any way whatsoever.

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Last Updated: 4th June 2004
© 2004 by Bob Eager, Tavi Systems