Sorry for the long post, but I’m kind of at my wits’ end here.
I recently purchased a good amount of 14TB Easystores (WD140EDGZ) during Best Buy’s recent sale. As I began testing and integrating them into my existing NAS, I noticed a very odd pattern.
My experience is that there are (at least) two drive models, and they perform very differently during ZFS resilvers:
* Slow: WDC WD140EDGZ-11B2DA2
* No Issues: WDC WD140EDGZ-11B1PA0
My testing has been somewhat erratic, but here’s my methodology for burn-in:
1. Short SMART test
2. Full badblocks test
3. Short SMART test
After running 1 drive through (11B2DA2), I didn’t notice anything immediately odd, and put it into my NAS to start resilvering. The ETA for resilvering was ~3.5 days at about ~150MB/s. This should have been the first red flag, but as I didn’t have much experience with drives this large (I’m moving from 8tb to 14tb), and my pool is hovering above 80%, I chalked it up to older hardware and a massive amount of data. I did this with one more drive (11B2DA2), and then by chance, I shucked a 11B1PA0.
Resilvering times jumped to ~12h.
I immediately suspected SMR, and so I ran `fio` as detailed [here](https://operand.ca/2020/04/30/smr_drive_detection_and_benchmarking_with_fio.html) to compare the two models, but they benchmarked similarly, so that’s out, thankfully.
I then swapped a 11B2DA2 in my array that had taken ~3.5d with a fresh 11B1PA0 to rule out a drive bay issue – again, resilvering took ~12h.
Finally, I compared `smartctl` output for 2 11B2DA2 and 2 11B1PA0, after forcing them to output `Throughput_Performance` with `smartctl -t offline`.
I normally take SMART data with a huge grain of salt, but the results seemed telling:
2 Throughput_Performance 0x0004 146 146 054 Old_age Offline – 57
2 Throughput_Performance 0x0004 144 144 054 Old_age Offline – 64
2 Throughput_Performance 0x0004 132 132 054 Old_age Offline – 112
2 Throughput_Performance 0x0004 133 133 054 Old_age Offline – 108
I’m thoroughly confused by this, as I can’t get this performance hit to show up anywhere aside from ZFS resilvering and `Throughput_Performance`. Searching beforehand, I only found one similar [post](https://www.reddit.com/r/DataHoarder/comments/qrx6vd/throughput_performance_low/) by /u/OldWorlDisorder about this.
Does anyone else have any similar data or experience?
EDIT 11/19/21: I haven’t been able to come to a conclusion that I’m happy with on this. I’m going to just get some proper drives to replace the 11B2DA2 that I was shipped, since they under-perform for me. If anyone has any other thoughts or experience, or want me to run any tests, feel free to comment, but I’m giving up investigating for now. Thanks all for the comments.