When I run Ohai and return all attributes, it takes about 2 seconds:
$ time ohai > /dev/null
It ought to take much less time to calculate the json for only a single attribute, but it doesn't:
$ time ohai filesystem > /dev/null
It appears as if Ohai is executing all code and then filtering it down to only display the requested attribute. If this is the case, shouldn't it be possible to avoid executing code for unwanted attributes, thus speeding up Ohai in this case?