checking I/O skew

Database
Enthusiast

checking I/O skew

How can we check I/O skewed processing for a query?

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3 REPLIES
Teradata Employee

Re: checking I/O skew

You can check I/O skew in Viewpoint query portlets, Query Monitor for points in time and Query Spotlight over durations of time.

Enthusiast

Re: checking I/O skew

Is there any way if we can check it using DBC.DBQLogTbl ?

Teradata Employee

Re: checking I/O skew

Hi Moutusi,

there are columns for maximum I/O and average I/O to get the I/O skew:

max = MaxAMPIO

avg = TotalIOCount / nullifzero( NumOfActiveAMPs )

skewfactor is  (100 - (avg/max*100))

Same for CPU.

Regards,

Vlad.