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MongoDB Chunk size many times bigger than configure chunksize (128 MB)

By Dinesh

 

Shard Shard_0 at Shard_0/xyz.com:27018

{

data: '202.04GiB',

docs: 117037098,

chunks: 5,

'estimated data per chunk': '40.4GiB',

'estimated docs per chunk': 23407419

}

---

Shard Shard_1 at Shard_1/abc.com:27018

{

data: '201.86GiB',

docs: 116913342,

chunks: 4,

'estimated data per chunk': '50.46GiB',

'estimated docs per chunk': 29228335

}


Per MongoDB- 

Starting in 6.0.3, we balance by data size instead of the number of chunks. So the 128MB is now only the size of data we migrate at-a-time. So large data size per chunk is good now, as long as the data size per shard is even for the collection.


refer - 



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