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From Code Guy <isurulu...@gmail.com>
Subject Parameters related to Seek Time in a Hard Disk
Date Wed, 14 Sep 2011 10:02:04 GMT
Hi all,

I went through the StoreCostController implementation to get an idea of the
estimated costs for store/fetch operations.

public static final double BASE_CACHED_ROW_FETCH_COST = 0.17;
public static final double BASE_UNCACHED_ROW_FETCH_COST = 1.5;
public static final double BASE_GROUPSCAN_ROW_COST = 0.12;
public static final double BASE_NONGROUPSCAN_ROW_FETCH_COST = 0.25;
public static final double BASE_HASHSCAN_ROW_FETCH_COST = 0.14;
public static final int STORECOST_CLUSTERED = 0x01;
public static final int STORECOST_SCAN_SET      = 0x01;
public static final int STORECOST_SCAN_NORMAL   = 0x02;

I want to reduce the cost allocated to seek operations for
a particular test. Can anyone specify which of these costs are related to
the seek time?

-- 
Thanks and Regards,
Isuru

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