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


2 Answers


Occurs when a task is waiting for space in the log buffer to store a log record. Consistently high values may indicate that the log devices cannot keep up with the amount of log being generated by the server. Information from Microsoft®


Used to indicate a worker thread is waiting for a log buffer to write log blocks for a transaction

This is typically a symptom of I/O bottlenecks because other workers waiting on WRITELOG will hold on to log blocks. Look for WRITERLOG waiters and if found the overall problem is I/O bottleneck on the storage system associated with the transaction. Text taken from CSS SQL Server Engineers: http://blogs.msdn.com/psssql/archive/2009/11/03/the-sql-server-wait-type-repository.

Somewhat common

This wait is somewhat common for most instances

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

Prevalence of LOGBUFFER across the Spotlight Population

For 68 % of hours with this wait, average wait time is less than 6.8 ms

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

2391 instances contributed data to this chart

Latency Distribution of LOGBUFFER across the Spotlight Population