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  1. Documentation
  2. DOCS-16342

[SERVER] Investigate changes in SERVER-78657: Get rid of `getSplitCandidatesForSessionsCollection` and `minNumChunksForSessionsCollection`

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      Original Downstream Change Summary

      We are marking as deprecated the server parameter `minNumChunksForSessionsCollection`. It will be ignored internally.

      It should be worth documenting this for the user, so in the future this server parameter could be internally removed. The problem is that `minNumChunksForSessionsCollection` has never been documented externally, and it makes no sense to do it from now.

      I propose introducing a section called "parameter ignored/DEPRECATED" or similar in the docs and expose the `minNumChunksForSessionsCollection` there, with the possibility to extend this list in the future.

      Description of Linked Ticket

      Starting from v6.0, the balancer is distributing data based on the data size on shards and not merely on the number of chunks. Because of that, it is totally useless to presplit the session collection during balancing rounds and it's also counterproductive because (1) chunks will not be moved and (2) starting from v7.0 the auto merger will squash them back together.

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            joseph.dougherty@mongodb.com Joseph Dougherty
            backlog-server-pm Backlog - Core Eng Program Management Team
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              Created:
              Updated:
              Resolved:
              20 weeks, 2 days ago