Search results for query: SMR

Some WD Red use SMR with is problematic with ZFS (slow up to the point of getting errors). Also, RAIDz1 is not the same as hardware RAID5 (and terrible for running VMs on) and very slow on writes. There have been a few threads on this forum before on how disappointed people are when they move...

Yes, some errors can be fixed by rewriting (and the drive controller remapping the sector to available spares). Your drive uses SMR and is therefore not suitable for ZFS, which might also give errors even though the drive is fine.

I replaced the disk, and did a fill wipe on it writing all 0's on the diskthrough TrueNAS . When I ran a couple of the LONG SMART tests again I got no errors. This caught my eye. Is there a way to clear SMART test resuts? Can these errors be fixed my themselves when I wiped and wr-wrote to...

True has does use zfs but the scenario is pretty common as I found numerous how to videos. The zfs for truenas storage is going to be on dedicated drives connected to separate sata controller which I plan to pass trough to the VM. The vm and its data will be stored on proxmox zfs ssd though, I...

Proxmox Backup Server (like Proxmox VE) does not support ARM: https://pbs.proxmox.com/docs/installation.html Does TrueNAS use ZFS? Some WD Red drives are SMR and do not work well with ZFS. Also using ZFS on top of ZFS will be slow and wear out consumer SSDs really quickly.

You are right, that's a typo. I've meant CMR HDDs. SMR should be avoided when using ZFS (and in general...no matter what you are planning to do with them...aren't even suitable as a drive for backups because of the terrible write performance once you try to write more than several dozens of GBs...

Um, isn't SMR HDDs pretty much exactly the wrong kind of HDD? Western Digital got in trouble for slipping those into their NAS line(s?), which led to things going poorly for the unfortunate purchasers...

Worth thinking, not in my case though since I'm about to use small NVME drive (~250G). Mainly for PVE itself plus come LXC, later on perhapse 1-2 VMs. Additional (yet obviously internal) 2,5" drive mailny for storage purposes (small NAS, NextCloud). Just wondered if having (not hunting for one...

You could also use ZFS with proper Enterprise SSDs and SMR CMR HDDs. That way you could create your own kind of hybrid storage by using the HDD for bigger data and an partition of your NVMe SSD for storing all metadata and smaller files. Have a look at the ZFS "special" vdevs.

What ST8000? Something like a ST8000DM004 uses SMR and shouldn't be used with ZFS or any raid or server workload. Write performance of SMR HDDs will drop to a horrible level once the caches got filled up. Especially terrible in case of a resilver where you need to rewrite the wholedisk continously.

Thanks! That's a good answer. I'll take a look on the topics you mentioned.

...not rolled out yet. You will have to wait for it or destroy and recreate your pool. By the way...those HDDs use shingled magnetc recording (SMR) and shouldn't be used with ZFS...or any other server workload... I would recommend you google for the difference between CMR and SMR and why SMR...

I know, but these were in the old server, no worries, as said, the new server is composed of : - 12 disks HGST SAS 7200rpm of 14TB - 2 SSD Samsung SAS 7.68TB I want to know how would you go forward with RAID 10 on the 12 disks, ZFS or Hardware RAID knowing the setup i described and my use case...

Those are SMR HDDs. Don't use SMR HDDs for anything if possible, especially not for server workloads or ZFS. CMR HDDs only exists up to 2.4TB in 2.5" form factor. Once the CMR-cache is full those SMR HDDs will totally suck and can't keep up writing.

Well, for that use case as long as they're not QLC based nand you'll probably be ok. :) The product brief doesn't seem to specify the nand type, which is a bit concerning. Given how dodgy WD tends to be when trying to save a buck that could mean they'll be playing fast and loose with the nand...

When I try copying data from a second drive in the PC (HDD) to the system drive (SSD), the transfer speed is constant and around 100 MB/s (tested on a 4 GB file).

Maybe the problem is on the other end (like a QLC SSD or SMR HDD)? What if you copy a file within the server or to another PC or to a RAM-drive?

What kind of WD drives? Unless they are WD Red Plus (or other enterprise drives) they could be using SMR (instead of CMR), which is also unusable slow with ZFS.

Hmmm, several Amazon reviews (here) are saying that model of Toshiba drive uses SMR technology. SMR is... to put it bluntly, absolute dog shit for performance. Pretty much worst possible technology. :( :( :( More info about SMR here, if that helps...

...product info for the 1TB and 2TB drives in that series (here), but nothing definitive for the 4TB one. Can't even tell if they're using CMR or SMR, which is of critical importance performance wise. IF those 4TB drives use SMR, you'll probably need to go and find some alternative drives that...