[SERVER-71158] getShardDistribution does not properly support sharded timeseries collections - MongoDB Jira

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Assigned Teams:

Sharding EMEA
Operating System:
ALL
Steps To Reproduce:

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1. Create a shareded timeseries collection
2. Invoke getShardedDistribution() against the namespace - this will return "Collection ts is not sharded"
3. Invoke getShardedDistribution() against the corresponding system.buckets.ts collection - this will yield NaN for docs per chunk and docs (total)

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1. Create a shareded timeseries collection 2. Invoke getShardedDistribution() against the namespace - this will return "Collection ts is not sharded" 3. Invoke getShardedDistribution() against the corresponding system.buckets.ts collection - this will yield NaN for docs per chunk and docs (total)
Sprint:
Sharding EMEA 2023-04-17, Sharding EMEA 2023-05-01, Sharding EMEA 2023-05-15
Case:

As of v6.0.2 the getShardDistribution() is not able to recognize a sharded timeseries collection:

[direct: mongos] test> db.weather.getShardDistribution()

MongoshInvalidInputError: [SHAPI-10001] Collection weather is not sharded

If invoked against the buckets collection, this will show some details, but a number of fields yield NaN:

[direct: mongos] test> db.system.buckets.weather.getShardDistribution()

Shard shard01 at shard01/localhost:27018

  data: '718B',

  docs: undefined,

  chunks: 1,

  'estimated data per chunk': '718B',

  'estimated docs per chunk': NaN

---

Totals

  data: '718B',

  docs: NaN,

  chunks: 1,

  'Shard shard01': [ '100 % data', 'NaN % docs in cluster', '0B avg obj size on shard' ]

This appears to be an oversight as the expectation is that getShardDistribution() should be able to recognize a sharded timeseries collection.

depends on

MONGOSH-1447 getShardDistribution does not support sharded time series collections

SERVER-76976 Programmatic API to get information on sharded collections