In a recent customer escalation we observed that a column backfill could cause a significant latency impact on a cluster that is running close to it's theoretical disk bandwidth limit. The backfill saturates the disk, latency climbs, admission control kicks in and the application traffic has a performance hit.

We should build a roachtest or benchmark to reproduce this type of behavior, so we can that use that as a platform to test and develop fixes. One such fix was propose in #82556, there is also a hypothesis that #82440 will help.

Jira issue: CRDB-16600

Epic CRDB-14607