amogh-jahagirdar commented on code in PR #16025:
URL: https://github.com/apache/iceberg/pull/16025#discussion_r3930888578


##########
format/spec.md:
##########
@@ -1385,6 +1496,20 @@ At most one deletion vector is allowed per data file in 
a snapshot. If a DV is w
 
 [puffin-spec]: https://iceberg.apache.org/puffin-spec/
 
+#### Manifest Deletion Vectors
+
+A manifest deletion vector marks entries in a leaf manifest as not live by 
encoding their positions in a bitmap. A set bit at position P indicates that 
the entry at position P in the referenced leaf manifest is not live.
+
+Manifest deletion vectors are encoded using the [Mumbling bitmap 
spec][mumbling-spec] and stored inline on the root manifest entry that 
references the leaf manifest. The snapshot in which the vector last changed is 
recorded in `tracking.dv_snapshot_id`; the three bitmaps are:
+
+* `manifest_info.dv`: every position not live as of that snapshot. 
`manifest_info.dv_cardinality` is its cardinality.
+* `tracking.deleted_positions`: the positions deleted in that snapshot.
+* `tracking.replaced_positions`: the positions replaced in that snapshot.
+
+`deleted_positions` and `replaced_positions` are disjoint.

Review Comment:
   Not really sure this needs to be said



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