TMF Application Programmer's Guide (G06.24+)

TMF ARLIB2 Audit-Reading Procedures
HP NonStop TMF Application Programmer’s Guide—522419-004
5-13
Distributed Transactions
Figure 5-1. Basic Parent-Child Relationship
In Figure 5-1, the transaction begins at node \A. The requestor running in node \A
sends a work-request message to a server in node \B. The processes in both nodes
generate updates to audited data files. When the requestor in node \A is ready to
commit the transaction, a phase one commit message is sent to node \B.
When node \B is ready for the transaction to be committed, the audit on node \B is
flushed to disk and a reply is sent back to node \A. The transaction then commits on
node \A, and node \B is notified that the transaction is to be committed. At that point
the transaction also commits on node \B.
The commit record on node \A contains a list of its offspring, node \B in this case. You
can retrieve this list of child nodes by calling the ARFETCHCHILDNODELIST
procedure after reading the commit record.
Figure 5-2 shows how the basic relationship between a parent and a child node gets
expanded for more complex transactions.
Node
Begin
transaction
End
transaction
Messages
r request
c1 commit phase 1
r1 reply to c1
c2 commit phase 2
Audit Records Generated
C commit
P network prepared
U update
\A
r
UU
c1
C
c2
\B U
U
P
r1
C
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