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


Waiting for responses to conversational messages (which require an explicit response from the other side, using the AlwaysOn conversational message infrastructure). A number of different message types use this wait type. Information from Microsoft®

Very rare

This wait never occurs for most instances

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

Prevalence of HADR_DB_OP_COMPLETION_SYNC across the Spotlight Population

For 92 % of hours with this wait, average wait time is less than 1.3 seconds

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

2 instances contributed data to this chart

Latency Distribution of HADR_DB_OP_COMPLETION_SYNC across the Spotlight Population