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A few other alternatives to the partition metadata file were considered. One topic of discussion was whether it was necessary to include at all. With the current decision of maintaining the topic name in the directory, the only way to persist the topic ID to disk is through a file. The decision against changing the directory is discussed belowAs discussed above, the directory changes will not be added until a major release.

The file can also be used for tooling purposes, and may contain mappings that will be useful in the future.

Another alternative is to have a single file mapping all topic names to ids. Although this could be useful for tooling, it would be harder to maintain this file and update on each new topic added. 

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