I am running MongoDB 4.2.0 on Ubuntu 18.04.3 LTS, single server, no replicas. This is hosted in AWS on a m4.4xlarge instance type (16 cores, 64GB RAM) with 2.5TB volume (type io1, 8000 IOPS). The CloudWatch metrics look completely normal. CPU usage seems to be between 20-25%.

After upgrading to 4.2.0 I started observing abnormal growth of WiredTigerLAS.wt. The only way to reclaim disk space is to restart the service. This needs to happen every day or two. In just under two days it has grown to 270GB. This can hardly be considered normal.

I am willing to share diagnostics data to get to the bottom of this.

I have found a similar issue but it does not seem to apply. Also, I do not see a resolution in the existing issue.