Blocked By Max Concurrent 32 Error For Many Users On MMP System (Doc ID 2454439.1)

Last updated on MAY 06, 2021

Applies to:

Symptoms

An error saying "blocked by max concurrent 32" occur for a lot of users over a 24 hour period on the MMP. This error is triggered after a DNS outage.

In the absence of dbhang/pstack output, it is not known whether:

• AService had threads stuck trying to connect, therefore the counter was accurate and threads were hung

or

• The counter got out of sync somehow

Also, similar DNS problems occurring world-wide and it is interesting that only these two systems had the MMP hung this way.

Until these two MMPs were restarted, they would generate messages like this:

at a rate of 130,000 to 150,000 per hour.

Cause

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