Re: How do enqueue waits affect overall db performance?

Dave wrote:
>
> Hey all,
>
> I have a DB with a large number of enqueue waits, taking up about 77%
> of the wait time in a statspack snapshot of 25 minutes. After some
> research its basically because of some distributed transactions over
> db_links. All the blocking locks that I can see are DX.
>
> Event Waits Time (s) Ela Time
> ------------- -------- ------- --------
> enqueue 1,372 4,115 77.71%
>
> How will this affect over all db performance? ie, I have another app
> in the same database.. Will this affect them? If so, how can I
> measure it..?
>
> tnx.
>
> Dave

Enqueue waits are transaction locks. The longer your transaction has to wait for a lock to be released, the worse it is for application performance. Another app on the same database may not contribute to this problem since the enqueues may be on different database objects. But it can be tough to say for sure until you deploy the other app.

HTH,
Brian

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