The wiredTigerConcurrentWriteTransactions and wiredTigerConcurrentReadTransactions server parameters can't be set via the db.adminCommand() helper directly.
For example:
MongoDB shell version v5.0.2
MongoDB server version: 5.0.2
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MongoDB Enterprise > db.adminCommand({ setParameter: 1, wiredTigerConcurrentWriteTransactions: 256 })
{
"ok" : 0,
"errmsg" : "Did not consume whole string.",
"code" : 9,
"codeName" : "FailedToParse"
}
Casting the value to either NumberInt or NumberLong addresses this:
MongoDB Enterprise > db.adminCommand({ setParameter: 1, wiredTigerConcurrentWriteTransactions: NumberInt(256) })
{ "was" : 128, "ok" : 1 }
MongoDB Enterprise > db.adminCommand({ setParameter: 1, wiredTigerConcurrentWriteTransactions: NumberLong(256) })
{ "was" : 256, "ok" : 1 }
Note this does not reproduce in mongosh:
Using MongoDB: 5.0.2
Using Mongosh: 0.15.6
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Enterprise test> db.adminCommand({ setParameter: 1, wiredTigerConcurrentWriteTransactions: 256 })
{ was: 128, ok: 1 }