Just a reminder to all of you who are already on MPE/iX 6.0 or are thinking
of upgrading to 6.0.

This doesn't include anyone on 5.5 or 6.5, only MPE/iX 6.0 with no PP, PP1
or PP2.

I sent a message to the list back in late February about a potential problem
with 6.0 and a possible fix available within VOLUTIL.  Since that time we
have repaired a lot of IMAGE databases on 6.0 machines which possibly could
have benefitted from this new VOLUTIL feature.  As the old saying goes: "an
ounce of prevention...."

Here is the important part of my message from February:

>While attending SigSoftVend last week I was talking to a CSY lab engineer
>and mentioned these 2 occurrences.  He wondered whether both clients were on
>6.0.  Long story short, he believes that there is a corner case bug within
>the new XM code for 6.0 which he is now going to develop a patch.  Until
>that patch becomes available, he mentioned that users of 6.0 could utilize a
>new feature on 6.0 (and only 6.0) within the XM which would prevent the
>problem from happening.
>
>In the 6.0 Communicator on page 216 there is an article on Transaction
>Manager.  On page 219 within the article there is a section entitled
>Checkpoint Improvement which describes 2 new commands in Volutil for showing
>and setting this new feature.
>
>In checking the last years worth of messages on 3000-l there have been a few
>references to this option. Mike Hornsby asked about it in February of 1999
>and Steve Macsisak with HP had a good description of it on February 19th
>1999.  Carl McNamee mentioned it favorably back in November of 1999.
>
>By default this option is disabled when you install 6.0 and if you enable it
>for your volume sets then you should not experience the problem mentioned
>above and you may even see a performance improvement on Checkpoints within
>the XM.  The 2 commands are:
>
>showchkptstat <volset-name>
>
>alterchkptstat <volset-name> ENABLE|DISABLE
>
>A key paragraph on page 220 then states:
>
>"Since this solution remembers the dirty page ranges in a data structure
>associated with each open file, it can't affect files that were open before
>giving this request (ENABLE).  However, it will come into effect for the
>files that were open (for the first time) after giving the request.  So the
>best way to enable or disable the Checkpoint Improvement is to reboot the
>machine after giving the command."
>

Hope this helps,

+---------------+
|               |
|            r  |  Ken                             [log in to unmask]
|          e    |                           http://www.adager.com
|        g      |  Ken Paul                      Tel 208 726-9100
|      a        |  Customer Support              Fax 208 726-2822
|    d          |  Adager Corporation
|  A            |  Sun Valley, Idaho 83353-3000            U.S.A.
|               |
+---------------+