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Chris Saxon

Thanks for the question, Vu.

Asked: March 15, 2023 - 4:28 pm UTC

Last updated: March 29, 2023 - 1:14 pm UTC


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You Asked

Hi Tom,

While checking ASH, I found some SELECT queries blocked other transactions with LATCH FREE with latch# = 39, which is "object stats modification". Can you explain what that particular latch is for and in which area it stays ?


and Chris said...

The wait is to do with populating segment statistics in AWR. While you can disable this (see MOS note 2778826.1), it's better to figure out which statements are causing this and get a fix for these.

If this is a significant issue - i.e. it's notably slowing down your transactions - please take this up with support.

Thanks to Mike Hallas for helping with this


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That explains a lot for me.

Vu Pham, March 28, 2023 - 9:07 pm UTC

Thank you. It is really helpful.
Chris Saxon
March 29, 2023 - 1:14 pm UTC


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