On Thu, Apr 22, 2010 at 9:13 AM, Khelben Blackstaff <eye.of.the.8eholder@xxxxxxxxx> wrote: >> I believe that these disks only come in the "green" variety. I recently >> picked up a 1.5 tb version for testing and cheap bulk storage, and I >> would not suggest using them in a raid array because the green drives >> firmware automatically parks the head after 8 seconds of inactivity and >> reduces the rpm of the disk. The constant parking can quickly wear out >> the head under high use and there is no way to disable this "feature". > > As previously mentioned wdidle utility can disable the head unloading. > >> The specifications say it's good for 300,000 cycles, so do the >> math... getting 5 unloads per minute would lead to probable failure >> after 41 days. Granted that is about worst case, but still something to >> watch out for. In order to make it the entire 3 year warranty period, >> you need to stay under 11.4 unloads per hour. If you have very little >> IO activity, or VERY MUCH, then this is entirely possible, but more >> moderate loads in the middle have been observed to cause hundreds of >> unloads per hour. > > WD mentions in the customer help (Answer ID 5357) that these newer drives > were validated to 1M load/unload cycles and not 300K. > >> >> If you want to fix it, then wdidle3.exe worked for me. Search for: >> >> wdidle3_1_00.zip >> I just looked at a WD green drive that was in a RAID1 set for several months. The drive is an older model -- WD10EADS, but I think similar. I did not use the widdle utility and the S.M.A.R.T. data reports a load cycle count of 42. The RAID set held user directories, so it was either under constant access (daytime) or not at all (nighttime, apart from during backups). Simon -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
