Improving ONC RPC performance
The performance of a single client request is affected by various aspects of the client, the network, CICS® ONC RPC, the user-replaceable programs, and CICS.
- The client
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The client timeout interval must take account of the possible delays in dealing with a client request in CICS ONC RPC and in CICS.
If a client request cannot be processed, an error reply is sent to the client.
- The network
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This manual does not deal with performance problems of TCP/IP networks.
- z/Os Communications Server resources
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If, while registering 4-tuples, you cause the connection manager to register too many 3-tuples with z/OS® Communications Server, you might reduce the service that CICS ONC RPC can give to incoming client requests.
- CICS ONC RPC
- The allocation of different alias transaction names to different 4-tuples must be coordinated with the priorities given to the transactions in CICS.
- The converter URM
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Getlengths is called only by the connection manager, and has no effect on the performance of a single client request, or on throughput.
Decode is called by the server controller. Delays here can reduce the throughput of CICS ONC RPC as well as reducing the performance of a single client request. The following recommendations are made:- Do not use CICS trace here except to solve specific problems.
- Use NOSUSPEND on EXEC CICS GETMAIN. If GETMAIN errors occur because there is not enough storage, look for solutions that do not involve using the SUSPEND option.
Encode is called by the alias. Delays here reduce the performance of single client requests, but not the throughput of CICS ONC RPC.
- The resource checker URM
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The resource checker is called by the alias, so delays here affect the performance of a single client request, but have no effect on throughput.