G
George Potemkin
Guest
If I understand correctly, the activity of idxactivate consists of: 1. Record reads using a base index (“useindex”); 2. Index key reads from the uncompleted tree of the activated index; 3. Creating in memory the recovery notes for the index blocks. Idxactivate does not write BI blocks, it’s a duty of BIW process. Transaction size (the "recs" option of idxactivate) or bi cluster size may affect the result but it's an indirect influence and it can be more or less eliminated. So the main activity is a reading, me think. Did anybody compare the idxactivate time with the time to read a table using a base index and/or the activated index? My guess: idxactivate is faster than idxfix 4. Cross-reference check of multiple indexes for a table (if you will select two indexes – the base and activated ones). Note that idxfix supports the -rusage option. And, of course, the reading tests require to empty the database and filesystem caches.
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