[CASSANDRA-8721] expose "shadowed" columns in tracing output

• Type: Improvement
• Status: Open
• Priority: Low
• Resolution: Unresolved
• Component/s: Legacy/Observability
• Assignee: Unassigned
• Reporter: Robert Coli
• Created: 02/Feb/15 21:51
• Updated: 16/Apr/19 09:31

Description

Current tracing messages expose how many tombstones are read in order to read live columns, but they do not expose shadowed columns. Shadowed columns are columns where the timestamp for a given column is lower than the highest timestamp for that column.

It would be useful for users who are tracing queries to understand how many shadowed columns are being read-than-ignored.