The analyze_shard_key.js workload sets analyzeShardKeySplitPointExpirationSecs to 10 and ttlMonitorSleepSecs to 1. Based on HELP-30625, it may take more than 10 seconds for the $_analyzeShardKeyReadWriteDistribution aggregate command to start runnnig and reading the split point documents. Consequently, no split point documents are found (since they have already been deleted by the TTL monitor). To avoid this scenario, we should increase analyzeShardKeySplitPointExpirationSecs to a larger value.