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Archives of the TeradataForum
Message Posted: Mon, 05 Apr 2010 @ 13:13:06 GMT
Subj: | | Re: CPU Skew/IO Skew/Hot AMP Cpu |
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From: | | Anderson, Dirk |
1. CPU and IO skew are usually inter-related, but depending upon the type of work being performed, sometimes CPU usage will be high on one amp,
whereas I/O (block reads/writes) will be in the normal range, or vice versa.
2. It means the hot amp is doing 19.6 times as much work as the average amp. This is very skewed, but may be acceptable for a very small query
(for example, less than 5 CPU seconds). You always have to consider CPU skewing in relation to the size of the query. The larger the query, the
greater the impact of skew on the system.
Thanks.
Dirk Anderson
Architect Manager
Enterprise Information Management
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