OEM metric extension query duration limit

I have a situation with some repository side metric extensions: at some point I found them disabled on the deployed targets.

Trying to undeploy and then redeploy them didn`t work, after they were getting deployed the metrics were switched to disabled state again.

I am now starting to suspect that this issue is related with the query duration, in average is taking around 4 minutes. I created a copy of the metric extension where I added a parallel hint to the query so that duration dropped to under 2 minutes and the metric was no longer disabled for that particular test target.

Is anyone aware of any limit that is configurable for queries executed for metric extensions in OEM?

Thank you.

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