I've recently asked an as-yet-unanswered related question.
My question here is a bit different: I want to know the best way to add storage to a laptop-based system without sacrificing power efficiency or "material efficiency". By the last, I mean anything which would cause the storage elements to deteriorate more rapidly than necessary. The main example I can think of is if spindown happens too infrequently, or perhaps also too frequently, the lifespan of the drive in question may be reduced.
Currently I'm trying to figure out how to get an HP Simplesave 2.5" drive to behave reasonably well. Obviously this is not the optimal choice; it was a boxing week sale which may end up being taken back.
Various tests on it using
hdparm seem to indicate that it's not using the value of the
-S parameter, which is supposed to determine how long it waits to spin down. Instead, it seems to spin down after 10 seconds if the
-B option is set to 127 or less, and after a long period of time, or perhaps not at all, if it is higher. I mention this mainly because I'm not entirely convinced that these directives will tend to work as
man hdparm says they should even on drives mounted in proper USB enclosures. The manual does mention that newer enclosures tend to support these features.
The system tends to function mostly as a server, though does see occasional use as a media box. It may get suspended from time to time, or may end up being powered on and active (though idle) for months.
I'd like to have available the same sort of power management functionality that I would get with an internally-mounted HDD in a desktop (or rack-mounted?) server. This includes spinning down and/or sleeping the drive when the server is suspended.
So I'd like to know the best approach to finding an efficient storage solution. Are certain brands of enclosures better for this? Is it necessary to use a 3.5" enclosure, or at least one that is powered separately from the USB line, to get proper power management facilities? Or would I have use a full NAS system for that?