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Home -> Community -> Mailing Lists -> Oracle-L -> DBWR Mystery
Hi ..
I am getting confused with the following DBWR related TAGs .
50 kcbswc DB writer IO clump
16 kcbscc DB writer checkpoint clump
13 kcbsdl DBWR blocks to scan lowest value
50 kcbsdh DBWR blocks to scan highest value
5 kcbsdi DBWR scan depth increment
50 kcbsfs foreground blocks to scan looking for free
200 kcbnbh number buffer headers
247 kcbnbf number buffer objects
Total number of buffers =200 and the DBWR Write batch size is 50. (i.e IO Clump).. But there are two more otehr tags (kcbsfs and kcbsdh) are also 50. Does that mean DBWR will scan so buffers (kcbnbh/4) all the times whenever you need a free buffer in the hash chain. And what is the difference between kcbscc and kcbsfs.(both are kcbnbh/4 here).
And the other point of confusion here is the difference in checkpoint clump and IO clump. What parameter (or algorithm ) used in deciding the kcbsdl and kcbscc .
I am using Oracle 8.0.3 with no buffer pools configured if that matters.
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