Hello @pooja_bhumandla ,

Even after setting delta.targetFileSize to 100MB, it’s normal to still see smaller files after OPTIMIZE. That setting is only a guideline, not a hard rule. Delta makes a best effort but won’t force all files to match the exact size.

Small files may remain for example due to:

1. Small partitions that don’t have enough data to merge further.

2. Delta avoiding row splits or large shuffle costs during compaction.

3. ZORDER (if used), which keeps files aligned to data layout for faster queries.

So, Delta prioritizes correctness and performance over strict file size, and this is expected behavior.

You can read more about a relevant docs here:

https://docs.databricks.com/aws/en/delta/tune-file-size

https://docs.delta.io/latest/optimizations-oss.html

Hope that helps. Best,Ilir