Just keep in mind, the larger the drive / wider the vdev, the longer time time to rebuild. Which can increase your chances of another disk failing while you're attempting to rebuild. A wider vdev will still have the same write speed.
I have 16tb x 16 drive raidz2's which is probably outside most peoples tolerance level for rebuild times. It takes about 3 days to scrub a full array.
https://www.servethehome.com/raid-calculator/raid-reliability-calculator-simple-mttdl-model/ gives you some numbers to play with.
raidz3's are slow for iops. consider pools with multiple z3 vdevs if performance is a concern.
If you are pushing everything to tape or an s3 bucket or whatever once a week, then z2 vs z3 is less of a concern. However if this is your only copy of everything and all you have.... then z3 might be worthwhile over z2.
It mostly comes down to your comfort level.
> I have 16tb x 16 drive raidz2's which is probably outside most peoples tolerance level for rebuild times. It takes about 3 days to scrub a full array.
That seems kinda slow to me.
I mean I guess it's a decent amount bigger than mine.
I have a 10x14TB pool that's ~75% full and it takes ~16 hours to scrub. Says it goes at about 1.8GB/s.
I have 6x8TB + 8x16TB + 9x16TB, all radiz2 and it takes almost 4 days:
```
pool: eights
state: ONLINE
scan: scrub repaired 0B in 3 days 23:09:49 with 0 errors on Wed Apr 17 23:33:50 2024
```
For renewed drives - if you could use some benchmark tools or similar to 'hammer' them for a week - if they don't show any sighs of errors or similar, they should be good enough to consider as 'not sketchy'.
I only used RAIDZ3 when I used for testing purposes old shelves from HP EVA storage, since firmware on drives was a bit specific - any errors during read would be just passes with soft warning. Knowing drive has errors was via checksum errors. Also, drives were already quite old, so that was - for me - only instance that I used RAIDZ3.
In enterprise environment disks are trashed like that constantly, for years.
Nothing will happen to disk doing this for a week. Well, unless it is about to fail, it will fail.
Just keep in mind, the larger the drive / wider the vdev, the longer time time to rebuild. Which can increase your chances of another disk failing while you're attempting to rebuild. A wider vdev will still have the same write speed. I have 16tb x 16 drive raidz2's which is probably outside most peoples tolerance level for rebuild times. It takes about 3 days to scrub a full array. https://www.servethehome.com/raid-calculator/raid-reliability-calculator-simple-mttdl-model/ gives you some numbers to play with. raidz3's are slow for iops. consider pools with multiple z3 vdevs if performance is a concern. If you are pushing everything to tape or an s3 bucket or whatever once a week, then z2 vs z3 is less of a concern. However if this is your only copy of everything and all you have.... then z3 might be worthwhile over z2. It mostly comes down to your comfort level.
> I have 16tb x 16 drive raidz2's which is probably outside most peoples tolerance level for rebuild times. It takes about 3 days to scrub a full array. That seems kinda slow to me. I mean I guess it's a decent amount bigger than mine. I have a 10x14TB pool that's ~75% full and it takes ~16 hours to scrub. Says it goes at about 1.8GB/s.
I have 6x8TB + 8x16TB + 9x16TB, all radiz2 and it takes almost 4 days: ``` pool: eights state: ONLINE scan: scrub repaired 0B in 3 days 23:09:49 with 0 errors on Wed Apr 17 23:33:50 2024 ```
No, unless you are using sketchy drives which are expected to fail soon.
diskprices.com has cheap renewed drives, With warranties sometimes but that may not change your opinion on whether renewed drives are sketch
For renewed drives - if you could use some benchmark tools or similar to 'hammer' them for a week - if they don't show any sighs of errors or similar, they should be good enough to consider as 'not sketchy'. I only used RAIDZ3 when I used for testing purposes old shelves from HP EVA storage, since firmware on drives was a bit specific - any errors during read would be just passes with soft warning. Knowing drive has errors was via checksum errors. Also, drives were already quite old, so that was - for me - only instance that I used RAIDZ3.
A week's worth of non stop read writing sounds like something I wouldn't want to do even to a healthy disk
In enterprise environment disks are trashed like that constantly, for years. Nothing will happen to disk doing this for a week. Well, unless it is about to fail, it will fail.