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: Latch
SQL Server versions: 2000, 2005, 2008, 2008 R2, 2012, 2014, 2016, 2017

What is LATCH_EX?

1 Answer


Occurs when waiting for an EX (exclusive) latch. This does not include buffer latches or transaction mark latches. A listing of LATCH_* waits is available in sys.dm_os_latch_stats. Note that sys.dm_os_latch_stats groups LATCH_NL, LATCH_SH, LATCH_UP, LATCH_EX, and LATCH_DT waits together. Information from Microsoft®

Very common

This wait is very common for most instances

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

Prevalence of LATCH_EX across the Spotlight Population

For 54 % of hours with this wait, average wait time is less than 0.3 ms

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

3684 instances contributed data to this chart

Latency Distribution of LATCH_EX across the Spotlight Population