“WT_CONNECTION.open_session: only configured to support 20020”

Frankly speaking, the explanation provided in SERVER-30421 and SERVER-17364 is a bit vague and “hand wavy” to me but at least there are steps that could help mitigate it:

  1. Decrease idle cursor timeout (default value is 10 minutes):
    In mongodb.conf:

    setParameter:
  cursorTimeoutMillis: 30000

    Using mongo cli:

    use admin
db.runCommand({setParameter:1, cursorTimeoutMillis: 30000})
  2. Increase session_max: 
    storage:
  wiredTiger:
    engineConfig:
      configString: "session_max=40000"
Posted on February 22, 2018 at 9:26 am by sergeyt · Permalink
In: MongoDB

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