>> When moving from MVS version 1 level 8 server to level 13/14
>> we found administrative sessions began hanging, causing all
>> ADSM sessions to hang. It always occurs when executing
>> a macro containing:
>>
>> define node
>> define association
>> commit
>>
>> After reporting the problem via IBMLINK, I received the following
>> from IBM:
>>
>> ---------------
>> Mike, it turns out that we intentionally made a change in this area
>> due to potential deadlock, specifically having to do with REGISTER NODE
>> followed by DEFINE ASSOCIATION. We now require either a COMMIT after
>> each command in the MACRO, or the use of the ITEMCOMMIT command on the
>> server. Unfortunatly, we didn't document this very well. We are opening
>> a DOC APAR for this for ADSM Version 1 Release 1. It is better
>> documented in Version 1 Release 2, and Version 2 Release 1. Sorry
>> for the inconvenience.

Early this year the DEFINE ASSSOCIATION command was modified so that it
issues a warning message if a node name is explictly listed in the
command but that node is not registered.  This was done to alert
an administrator who might have mistyped one node name in  a list
(see APAR IC08618).  To implement this change, the DEFINE ASSOCIATION
command was altered so that it serializes on a resource that is
also used by the REGISTER NODE command.

As a side effect of this change, when the REGISTER NODE and
DEFINE ASSOCIATION commands are both used in a macro, it became
necessary to make sure that the REGISTER NODE command is committed
before the DEFINE ASSOCIATION command is issued.  This can be done
using a COMMIT statement or the ITEMCOMMIT option.

Several months ago, the DEFINE ASSOCIATION command was again modified
to eliminate the interaction between the REGISTER NODE and DEFINE
ASSOCIATION commands.  With this fix, the warning message which
was added for APAR IC08618 will still be issued, but it will no
longer be necessary to commit the REGISTER NODE command before issuing
the DEFINE ASSOCIATION command.  The fix will be applied to all
server platforms and releases.  For the MVS Version 1 server, the
fix will appear in PTF 15.

Because of the potential for such interactions between commands within
a macro, we recommend the use of COMMIT or ITEMCOMMIT in situations
where commands within a macro behave differently than the same
commands issued from the command line.  The documentation APAR is
intended to explain to Version 1 customers that such interactions
can occur and will document the recommended use of COMMIT and ITEMCOMMIT
if problems with macros are encountered.  The Administrator Reference
for V1R2 and V2R1 already contains this information.

Dave Cannon
ADSM Development