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 access to the cache of compressed log blocks that is used to avoid redundant compression of the log blocks sent to multiple secondary databases. Information from Microsoft®

Very rare

This wait never occurs for most instances

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

Prevalence of HADR_COMPRESSED_CACHE_SYNC across the Spotlight Population

For 71 % of hours with this wait, average wait time is less than 0.02 ms

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

87 instances contributed data to this chart

Latency Distribution of HADR_COMPRESSED_CACHE_SYNC across the Spotlight Population