September 25, 2008 at 2:24 pm
Quick question,
Is total worker time dependent on the # of CPU's? Like if I have 8 CPU's, and I assume that everything is evenly spread across processors, would i divide total_worker_time/4 to get the aprroximate duration?
October 3, 2008 at 6:23 pm
No. Total_worker_time is nothing but CPU count. No need to divide. Its the amount of CPU your process used thats it.
June 14, 2012 at 12:49 pm
Nikhil Shikarkhane (10/3/2008)
No. Total_worker_time is nothing but CPU count. No need to divide. Its the amount of CPU your process used thats it.
Does it matter if my MAX DOP is 1 or > 1?
July 2, 2012 at 5:54 am
total_worker_time is sum of time taken by all CPU's ,for all the execution of that particular query... see execution_count...If you divide toatl_worker_time by execution_count it will give you average worker time (which is sum of all CPU's based on you maxdop) for that query.
if you want to look for a particular instance try for the last_wo0rker time( This is for the latest execution).You can not say that each of the 4 cpu will use the same time. It might be possible that one is taking 10 ms and other 3 are taking 100ms each.. So do not try to draw any conclusion from that. Only conclusion you can draw from this is that total cpu time for a last execution of the query is the last worker time.
Also, the same query plan might be executed with diff maxdop based on the worker threads at runtime. Thus a query can run with maxdop 4 first time might run with 3 cpu next time...
GulliMeel
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