Local and Remote File Query Performance

The following screen shots of the CONNX InfoNaut Query application demonstrate differences in response time for SQL queries against identical local and remote CICS VSAM KSDS files:

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As the records per second counts (114 vs. 78) demonstrate, the same SQL query executed against identical local and remote VSAM KSDS files runs faster against the local file. CONNX SQL query performance against remote VSAM KSDS files can be optimized by importing index information from corresponding local files, if available. Once the key information is provided for remote files, CONNX executes the same file traversal logic for both local and remote files. The remaining differences in performance measures such as records per second derive from the MRO or ISC link overhead between the CICS regions.