I have a home server with a Western Digital Caviar Green WD20EARS 2TB disk in it. Recently, I’ve come across this post explaining that this drive’s IntelliPark parks the head after only 8 seconds of being idle. Linux by default caches disk access for 30 seconds on an idle system, leading to up to 120 load/unload cycles per hour!

I was not able to actually see the head load/unload on my system when I looked at it for a few minutes, but the SMART-data clearly shows that it has been happening a lot over the past 22 months:

193 Load_Cycle_Count        0x0032   151   151   000    Old_age   Always       -       147669

Almost 150000 park/unpark cycles! That’s on average more than 9 per hour!

Western Digital provides an “Idle Mode Update” tool (local copy of v1.05) that is capable of changing this 8 second timeout to a more reasonable value. I used this guide to make a useable USB drive to boot DOS from (local copy of ubbe).

I’ve changed the timeout to 300 seconds or 5 minutes, which seems much more reasonable.