Description

Before 4.2 MMAPv1 options used with WT were just ignored.

In 4.2 the server won't start if MMAPv1 options are used:

Error parsing command line: unrecognised option '--smallfiles'
try '/bin/4.2.0/mongod --help' for more information

We should document that in the release notes

Scope of changes

• Add a blurb to the 4.4 release notes on MMAPv1 removal. Spitballing:

"4.4 mongod or mongos cannot start with MMAPv1 options specified to the command line or configuration file "

• Add blurb to 4.0 -> 4.2 upgrade notes reminding users to remove MMAPv1 options from the command line or configuration file as part of upgrade
  • Upgrade note needs to be in master and 4.0.

Impact to Other Docs

MVP (Work and Date)

Resources (Scope or Design Docs, Invision, etc.)