What Does Activity Monitor Do?

Tibor Karaszi explains each window in the Management Studio Activity Monitor:

The idea here is to show where SQL Server is waiting, “wait stats”.

It uses the same procedure as the “Waiting Tasks” diagram uses, #am_generate_waitstats, to get the information. See the above section for “Waiting Tasks” to understand the time dimension for this. For simplicity, we can say that it shows only wait stats for the past 30-60 seconds. This is important. Imagine that you had loads of a certain wait stats, but none just for the last minute. This pane can now fool you that you didn’t have any waits of that kind, just because you didn’t for the past minute. Note, though, that the “Cumulative Wait Time” column is the sum of wait in the group since SQL Server was re-started or since we last cleared the wait state (DBCC SQLPERF(“sys.dm_os_wait_stats”,CLEAR)).

In an attempt to be friendly, it will group and summarize wait stats into various groups. That would be fine if there were some documentation about which individual wait type is in each group. Also, some wait types are ignored. One of the ignored wait types is CXPACKET, another is THREADPOOL.

Activity Monitor isn’t very good, but sometimes you can’t get the good tools installed on a server and need to check something quickly.  In those cases, it’s a handy thing to know.

Related Posts

Management Studio’s Staying Power

Kendra Little explains why SQL Server Management Studio isn’t going away anytime soon: After all, SSMS is no longer the cool new kid on the block: Microsoft has shown consistent effort to develop their new tool, Azure Data Studio (the artist formerly known as SQL Operations Studio), since November 2017. Azure Data Studio is built on the […]

Read More

Change Tracking in SQL Server

Tim Weigel covers the basics of change tracking in SQL Server: There aren’t a lot of parameters here. You can set change tracking on or off, you can specify your retention period, and you can specify whether to enable auto-cleanup or not. For the retention period, you have the choice of DAYS, HOURS, or MINUTES. […]

Read More

Categories

February 2017
MTWTFSS
« Jan Mar »
 12345
6789101112
13141516171819
20212223242526
2728