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HP Reliable Transaction Router User Manual

Page 33

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RTR Server Types

Concurrent server

The concurrent server is an additional instance of a server

application running on the same node. RTR delivers transactions

to a free server from the pool of concurrent servers. If one

server fails, the transaction in process is replayed to another

server in the concurrent pool. Concurrent servers are designed

primarily to increase throughput and can exploit Symmetric

Multiprocessing (SMP) systems. Figure 1–16, Concurrent

Servers, illustrates the use of concurrent servers sending

transactions to the same partition on a backend, the partition

A-N.
Concurrent servers allow transactions to be processed in

parallel to increase throughput. Concurrent servers deal with

the same database partition, and may be implemented as

multiple channels within a single process or as one channel in

separate processes. The application designer must determine

if transactions can be processed concurrently by the database

or server application. Deadlocks can occur if every transaction

competes for the same database lock outside the RTR server

application.

Figure 1–16 Concurrent Servers

VM-0835A-AI

BE

Server 1

Server 2

Server 3

Server 4

A - N

Partitioned Disks

Introduction 1–21