Subject Name Performance Considerations

When designing subject name conventions, remember these performance considerations:

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Shorter subjects perform better than long subjects.

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Subjects with several short elements perform better than one long element.

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A set of subjects that differ early in their element lists perform better than subjects that differ only in the last element.

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With certified delivery and distributed queue features, the cost of storage and accounting varies according to the number of subject names. We strongly discourage embedding one-time tokens (such as timestamps) within such subject names, because they can result in unbounded growth of storage and accounting costs. Instead, embed such one-time values within message fields.