Service Collection
By default, the Driver Service Instance collects results as soon as they are available. In some cases, you want to collect results at a later time, or never collect them. Service collection can be defined with the Service Option COLLECTION_TYPE. Possible values for COLLECTION_TYPE include IMMEDIATELY, LATER, NEVER, and AFTER_SUBMIT.Values used with COLLECTION_TYPE are as follows:
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Value |
Description |
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Collection does not begin until all tasks have been submitted. See Collect After Submit for more information. This enables optimal submission without network competition from the collection when the Service follows the “submit all, collect results” pattern. |
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Task outputs are collected as soon as they are ready. This is the default. |
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Task outputs are not collected in this Service. Another Service collects them later. See Deferred Collection (Collect Later) for more information. This is not available from a Service proxy. |
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Task outputs are not collected. See No Collection (Collect Never) for more information. This can be used, for example, in the case where a Service write data directly to a database. This is not available from a Service proxy. |
The LATER and NEVER collection modes are not for long-running Services. Use them only for batch submissions that finish quickly. If you use them for Services with indefinite duration, there is no way to clean up the inputs.