Common People
I know, you probably have questions about CXPACKET.
Maybe you look at a wait stats report and nod sagely at the caps lock extravaganza of variably descriptive names.
The unformatted numbers that you tally on your fingers, and then have to look up what 12 digits is.
When you search around, you can figure out what most of your waits are, and why they happen. You might even be able to figure out how to fix them.
(I know, you’re gonna read advice on a blog from 2003 telling you to set “MaxDOP” to 1, but forchrissakes don’t do it.)
What I’m looking for are waits that pop up, but you haven’t been able to find answers to. The real nut crackers.
If you’ve got those, leave a comment and let me know.
Going Further
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In our BI environment, LATCH_EX and SOS_SCHEDULER_YIELD with a ton of CX_PACKET. I am fairly sure it’s all connected. Almost all queries go parallel on this server. I’m pretty sure that LATCH_EX and CX_PACKET are the waits for the CPU exchanges that are happening. And SOS_SCHEDULER_YIELD due to the threads going full duration while accessing these hot pages. I could be making no sense at all too. But that’s how I feel pretty much all the time.
20% PWAIT_EXTENSIBILITY_CLEANUP_TASK on Azure SQL DB, and Paul has never hear of it.
Ditto for HADR_FABRIC_CALLBACK
||Wait_Type||Wait_Time_Seconds||Waiting_Tasks_Count||Percentage_WaitTime||
|SOS_WORK_DISPATCHER|170002332.987000|43004127|94.814702340907681|
|PWAIT_EXTENSIBILITY_CLEANUP_TASK|2280667.189000|7603|1.271987136083864|
|HADR_FABRIC_CALLBACK|2280634.252000|8456|1.271968766266250|
|XE_LIVE_TARGET_TVF|2280564.646000|38011|1.271929945198002|
|BACKUPIO|452693.435000|362505333|0.252447568217817|
on Azure SQL DB. Don’t know if it is a problem or not. If it is I have no idea how to solve it.
Google found only this blog.
Those sound like background tasks. I’d probably screen those out.