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: IO
SQL Server versions: 2008, 2008 R2, 2012, 2014, 2016, 2017


1 Answer


Occurs when a write operation is in progress. Information from Microsoft®

Very rare

This wait never occurs for most instances

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

Prevalence of WRITE_COMPLETION across the Spotlight Population

For 43 % of hours with this wait, average wait time is less than 0.63 ms

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

2260 instances contributed data to this chart

Latency Distribution of WRITE_COMPLETION across the Spotlight Population