So I just got a new Macbook Pro (2.9 GHz 13" specs) last week, which I'm absolutely in love with (especially due to the massive spec upgrade it is for me when compared to my mid-2009 Macbook), except this strangeness with my hard drive.
Basically, every few seconds to every few minutes I hear a soft "click" sound from the disk, akin to the sound of (I love this analogy) two mice playing ping-pong.
Curious and concerned as to what it all meant, I did some digging and learned that Mac HDD's (slash I think all modern disks) have what's called the Sudden Motion Sensor, which detects unusually strong vibrations (ex. music at a club) or sudden movements (ex. picking up your computer) and instantly parks the hard drive heads to help reduce the risk of damage to the hard drive in case of impact. And as you may already know, the sound of HDD heads parking is this aforementioned audible click, with each occurrence increasing the load cycle count of the disk by 1.
Now here's the caveat: as I was reading further, I discovered that the SMS is great in all Windows computers, but apparently has issues in Unix-based systems, resulting in hyperactive sensitivity, doing things like what I've experience: the parking of heads 10 times in 4 minutes while I'm reading a web page like Southperry, for example.
So how bad is it? According to the latest S.M.A.R.T. utility reading, my HDD is at 1984 load cycle counts in just about 55 power on hours. That, combined with the average 300,000 - 600,000 load cycle count capacity of most hard drives, means my hard drive risks an early death.
Bottom line: should I deactivate SMS or not? The pros of having it active are power saving/management, HDD protection, and prevention of HDD and computer overheating. The cons are a potentially early HDD failure and stutters in video and audio playback from constant parking.
Now of course I don't have my computer on 24/7, and even if plugging in 6 hours a day of use with the figures above the disk should still last roughly 7 years, but I'm just curious for anymore input you tech and computer-savvy denizens of Southperry may provide.