This line of code in the kill_rooted_or.js concurrency workload is subtly wrong:

populateIndexes(db[this].collName, this.indexSpecs);

The closing square bracket is in the wrong place. It should be written like so:

populateIndexes(db[this.collName], this.indexSpecs);

The workload still passes, but it is not doing what it was originally intended to do. As written, the call to populateIndexes() builds indexes on a collection named something like "[object Object].collName" as opposed to the collection named "kill_rooted_or" against which all the other test operations occur. We should fix the workload to build indexes against the correct collection.