![]() NAS and other enterprise drives have features to make them more reliable in harsher conditions (heat, vibration, operational knocks induced by hot swapping, etc.). Looks like the most differentiating factors between enterprise and consumer drives are the command sets they support and features they bundle. IIRC, it was around ~10 years old too with a much heavier workload history. At office, I changed an old Seagate Constellation ES.2 (aka Barracuda enterprise) drive since it started to develop bad sectors (which I removed from an old disk storage unit anyway). I've replaced two 11 year old WD Blacks w/o any problems this year to upgrade to two IronWolf Pro NAS drives, because I wanted something dense and PMR. If there's one trend I've seen from using generations of HDDs, excluding some problematic generations like first SATA Seagate Barracudas and early WD Caviars which died for no reason at all, newer generation HDDs are always more reliable from previous generation, regardless of their class (datacenter / consumer).įor the last 10 years or so (starting with the introduction of first WD Green / Blue / Black series), the HDDs are exceptionally reliable unless you abuse them on purpose (like continuous random read/write benchmarking). Sadly some drive firmware doesn't implement some or all of the above, so they appear to have "failed" and become unreadable, which IMO is inexcusable when it's very easy to design so that worn out drives become slow instead.ĭisclaimer: This is my personal experience from being an HPC sysadmin and old school computer enthusiast. Clearly thats going to be slow enough the drive will have stopped being used long before that. In the worst case, reading a single sector requires reading every sector on the drive to reconstruct. To fix that, you need to rewrite the data, which slows everything down more.Īnd now that you have a bunch of unreliable sectors, you also need "super-sectors" which can do sector-based hierarchical erasure coding to recover data from sectors where even the methods above have caused data to be lost. Worn out flash also doesn't hold data long - perhaps only a few hours before too many bits have flipped and it is unreadable. Now you have less than half the performance. It is possible to combine two sectors to have extra error correction data to still recover a sector. Thats because a "worn out" flash sector is never fully worn out - it can still store some data, just less than the error correction can correct. The drive also gets slightly smaller (by passing write failures to the OS to mark sectors bad). It will never get to failure because the slowdown gets so extreme it becomes unusable. A well written SSD firmware simply slows down with age.
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