TS/MP 2.5 Release Supplement

Table 2 Limits for Pathsend Requestors (continued)
TS/MP 2.5DescriptionParameter
8191Maximum outstanding send requests for all requestors in the
processor.
Requestors send
operation (per
processor)
4045Approximate maximum server classes to which all requestors
in a processor can have outstanding sends. The exact number
depends on the current memory utilization.
Server classes
NOTE: When both TS/MP for NonStop Tuxedo (TROUT) and TS/MP 2.x are installed on a
system, two link manager processes run on the system. The TS/MP 2.x link manager process runs
as $ZLnn using the $SYSTEM.SYSnn.ROUT executable file. The TS/MP for NonStop Tuxedo link
manager process runs as $ZTnn and uses the executable file $SYSTEM.SYSnn.TROUT. On such
systems, the limits applicable for TS/MP for NonStop Tuxedo are the same as for TS/MP 2.0. For
TS/MP 2.0 Pathsend Requestor Limits, see the TS/MP Pathsend and Server Programming Manual.
Table 3 (page 21) lists the Pathway Domain Limits.
Table 3 Pathway Domain Limits
LimitParameter
4Number of PATHMONs per Pathway domain
255Number of Pathway domains
NOTE: When Pathway domains are used the Pathway configuration limits are increased up to
four times because four Pathways can together form one logical Pathway environment.
For example, MAXSERVERPROCESSES is increased from 4096 to up to 16380.
Link Management
To provide transparent migration from TS/MP 2.0 applications, the ACS subsystem link management
functions use the same program filename ($SYSTEM.SYSnn.ROUT) and process name ($ZLnn)
used by TS/MP 2.0. However, because the contents of $SYSTEM.SYSnn.ROUT are different for
each version, the TS/MP 2.5 cannot be used in a TS/MP 2.0 environment, and vice versa.
Although there are changes in server class queuing, it is important that servers conform to the server
packaging guidelines outlined in Section 2, Packaging Server Functions in the HP NonStop TS/MP
2.5 Pathsend and Server Programming Manual. The changes described in this section are
recommended but not mandatory.
Grouping long-running and short-running requests cause uneven response time and increases the
number of links needed to maintain transaction throughput. If an application contains server
programs that process both long and short-running requests, configure the server program to use
multiple server classes in PATHMON. This separates the long and short-running requests into
different queues. You can modify requestor programs to call one server class for long-running
requests and another server class for short-running requests.
For example, consider a server that can perform simple queries and database updates. A database
update operation is generally long-running while a query is short-running. You can configure the
same server class as two server classes and program the requestor to send query requests to one
server class and the database update requests to the other. When all processes of a server class
are performing the same task, ACS can load balance the requests more effectively.
ACS takes the response time of a link into consideration while selecting the best possible link from
its pool of free links to satisfy a request. Also, ACS gives preference to static processes over dynamic
processes. The new algorithm used for link management might require more or fewer links to server
Link Management 21