private void AddBlankBTree(BsonDocument btreeOutput)
{
// We add a blank document, since the server is expecting
// these btree index values to be present.
btreeOutput.Add("accesses", 0);
btreeOutput.Add("accessesPS", 0);
btreeOutput.Add("hits", 0);
btreeOutput.Add("hitsPS", 0);
btreeOutput.Add("misses", 0);
btreeOutput.Add("missesPS", 0);
btreeOutput.Add("missRatio", 0D);
btreeOutput.Add("missRatioPS", 0);
}