Waitopedia is a comprehensive resource of information about SQL Server waits.

The description shown below is the top answer as voted by the Spotlight community.

The charts are based on 2.1 TB of data collected from 4207 instances uploaded by 323 Spotlight users over an 8 week period.


Category: Other
SQL Server versions: 2012, 2014, 2016, 2017


1 Answer


Database recovery is waiting for the secondary database to finish the reverting and initializing phase to bring it back to the common log point with the primary database. This is an expected wait after failovers.Undo progress can be tracked through the Windows System Monitor (perfmon.exe) and dynamic management views. Information from Microsoft®

Very rare

This wait never occurs for most instances

For each of 4207 instances, we ranked HADR_RECOVERY_WAIT_FOR_UNDO on how frequent it is compared to all other recent waits. The chart shows the total of all rankings.

Prevalence of HADR_RECOVERY_WAIT_FOR_UNDO across the Spotlight Population

For 17 % of hours with this wait, average wait time is around 100 ms

For each instance, we found all the recent hours when it had a HADR_RECOVERY_WAIT_FOR_UNDO wait. We found the average latency for each of those hours.

6 instances contributed data to this chart

Latency Distribution of HADR_RECOVERY_WAIT_FOR_UNDO across the Spotlight Population