4.2 When to Use MSSQ Sets (Oracle Tuxedo ATMI Servers Only)

Note:

Multiple Servers, Single Queue (MSSQ) sets are not supported in Oracle Tuxedo CORBA servers.

The following table describes when to use MSSQ sets with Oracle Tuxedo servers.

Table 4-1 When and When Not to Use MSSQ Sets

Use MSSQ Sets When	Do Not Use MSSQ Sets When
There are several, but not too many servers.	There is a large number of servers. (A compromise is to use many MSSQ sets.)
Buffer sizes are not too large.	Buffer sizes are large enough to exhaust one queue.
The servers offer identical sets of services.	Services are different for each server.
The messages involved are reasonably sized.	Long messages are being passed to the services causing the queue to be exhausted. This causes non-blocking sends to fail, or blocking sends to block.
Optimization and consistency of service turnaround time is paramount.	Optimization and consistency of service turnaround time is not critical.

The following two analogies help to show why using MSSQ sets is sometimes, but not always, beneficial:

• An application in which MSSQ sets are used appropriately is similar to a bank, where all the tellers offer the same services and customers wait in line for the first available teller. This efficient arrangement ensures the best use of available services.
• An application in which it is better to avoid using MSSQ sets is similar to a supermarket, where each cashier offers a different set of services: some accept cash only, some accept credit cards, and still others serve only customers buying fewer than ten items.