HDFS is unsupported

[alexey-milovidov]

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[robot-clickhouse-ci-1]

This is an automated comment for commit 39b84d0 with description of existing statuses. It's updated for the latest CI running

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[kssenii]

May be this message is too much? "At all" is not really true... If if did not work at all, there would have been no sense having hdfs in documentation at all.

[den-crane]

@kssenii latest HDFS have a hard limit 1million files (objects) per folder.
Clickhouse stores all objects in a single HDFS folder (for HDFS as external storage, unlike S3).
The average table with 500 columns reaches this limit of 1million objects easily, it's less than 1000 active+inactive wide parts, after that a table is unable to insert or to merge.

#43112