On Tuesday, 11/27/2007 at 11:39 EST, Alan Ackerman 
<[EMAIL PROTECTED]> wrote:

> The question is, when are two-phase commits used? From what others have 
told 
> you, one answer
> is when you have R/W  access to two different SFS filepools.

The reference to a "protected conversation" is an APPC LU 6.2 
SYNCLEVEL=SYNCPOINT conversation.  It has a two-phase commit semantic 
built into it.

Within a single CMS workunit you can, for example, open an SFS file (one 
file in one server, or multiple files, or multiple servers) and talk to 
one or more CICS LU 6.2 transactions (for example) over the network.  When 
your application or one of the CICS transactions COMMITs the workunit, all 
files and transactions are committed or all are backed out.

It doesn't matter whether you're doing this explicitly or not.  The CMS 
file system will try to connect to the CRR server in *anticipation* of 
your opening a second file or establishing a syncpoint connection.

Alan Altmark
z/VM Development
IBM Endicott

Reply via email to