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Archives of the TeradataForum
Message Posted: Thu, 21 Jun 2013 @ 01:00:25 GMT
Subj: | | Re: High AMP I/O Skew Always |
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From: | | Clark, Dave |
Sirupa Ashok-
The fact that this is always occurring and it is associated with a vproc would tend to indicate that you have a disk that is degraded. You
now know which node and which AMP is suspect. If you want to delve deeper, you can use the query below. I would run it against the
suspect AMP and another AMP on the same node for comparative purposes. I would expect to see a very high count for the outstanding request
(DiskoutReqAvg) which would be reflective of successive retries.
As I said earlier, you should consider opening an incident with the GSC. With the information in hand, they should resolve it very
quickly.
Regards,
-dave.clark
select cast((ProcId/32)*100 as integer) + (ProcID mod 32) (title 'Node',
format 'ZZ9-99')
,VprocNo (title 'Vproc',format 'ZZZ9')
,DiskUse (title '% Disk',format 'ZZ9.99')
,DiskReads (title 'Reads',format 'ZZZ,ZZZ,ZZZ,ZZ9')
,DiskWrites (title 'Writes',format 'ZZZ,ZZZ,ZZZ,ZZ9')
,DiskoutReqAvg (title '% Req Out',format 'ZZ9.99')
,PctService (title '% OS',format 'ZZ9.99')
,PctAmpWT (title '% Amp',format 'ZZ9.99')
from table (SYSLIB.MonitorVirtualResource()) as t2
WHERE VprocType = 'Amp'
AND VprocNo = xxxx <==== replace with vproc #
order by 1,2
;
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