G
George Potemkin
Guest
New questions: now about buffer locks and object blocks. Sessions that create new records (for example, in the "history" areas) obviously need to update the area's object blocks that store information about the chains and area's current HWM. Promon/Status: Buffer Locks did show 39 exclusive locks on the object blocks of 60,932 buffer locks caught at the snapshots - only on the object blocks in the areas with 4 history tables and with their indexes. It's the rare events - only when areas are extended. So far so good. But Promon/Status: Buffer Lock Queue show the queues to the object blocks: 10 processes in the average, 45 processes at the max are waiting for the same object block. Isn't it too much for the rare events? Do all of them try to extend an area? It's SHAREWAIT for the table's areas and EXCLWAIT for the index's areas. Why there is the difference? Why we did not catch at least one share lock on the object blocks but only SHAREWAITs? Results: (Please visit the site to view this file) (Please visit the site to view this file)
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