Transcend SSD boot disk - ZFS checksum errors

[jonatkins]

Hi,

I'm currently in the process of rebuilding an old FreeNAS box, reusing some components while others are new.

Initially I installed onto a USB drive, as was used in the old installation, but as I now have spare SATA ports (and the HW guide recommended it) decided to mirror this with an old HDD and switch the USB for a small SSD.

The USB + HDD mirror pair worked perfectly, no issues over the last week or so.

However, now I've switched the USB for a Transcend 16 GB SSD (TS16GSSD630), I've started getting checksum errors on the new SSD.

- If left for several hours, 5+ checksum errors are found/fixed by a scrub.
- Running a second scrub within seconds of this, and another checksum error is common.

Thinking faulty SSD, removed it from the mirror and ran additional tests.

- manual 'dd' read/writes all OK without errors
- 'badblocks' write+verify test has no errors.
- Attached the drive via a USB adapter to my desktop PC, formatted it as FAT32 and copied some files to it. All data read back successfully
- added it back to the boot mirror, and checksum issues persist.

So the only place I have actually reproduced the problem is as the FreeNAS boot device and ZFS checksum checks.

Any thoughts? Faulty SSD? (but why no issues with the other tests?) Known issue?

Jon

Edit: attached smartctl -a output. (Yes, I know attribute 167 is flagged as FAILING NOW - it was like that before I used the disk, but with a raw value of 1. Still, I can't reproduce the issues outside of a FreeNAS ZFS boot setup so don't think it's an issue)

 

[anmnz]

Sounds extremely similar to my report:

https://forums.freenas.org/index.php?threads/freenas-installer-sandisk-ssd-checksum-errors.64049/

and @capa 's:

https://forums.freenas.org/index.php?threads/boot-disk.63829/

 

[jonatkins]

Is your Kingston SSD still working fine? Might swap for one of those. Or maybe just a 2nd old hard disk for now.

I'll be able to experiment for the next week or so if anyone has suggestions of things to try.

 

[anmnz]

The Kingston is still fine. (Not that I had any reason to choose Kingston in particular, it was just cheap.)

 

[capa]

Any idea as to what controller is used in the Transcend SSD? I couldn't find anything on the internet (after only a quick search).

I had a similar problem with a SANDisk SSD Plus 2.5'' and a WD Green 3D Nand. Both turn out to have a Silicon Motion Controller SM2246 respectively SM2256 or some variant. I moved to an ADATA SP920 128 GB and had no problems since. This SSD features a Marvell controller. While trying to figure out the problem I also tried a 10 year old HDD (2.5'' SAMSUNG SpinPoint M5S 250 GB), and had now problems with it. Full report can be found here.

 

[jonatkins]

I had thought along those lines myself, but a search yesterday didn't find anything.

However, combining it with your hint of 'Silicon Motion', I found some positive results.

Another Transcend model range, SSD370, uses a Custom Silicon Motion SM2246EN (link), and I found a listing for another model in the SSD670 range I have saying it uses Silicon Motion too (link).

This seems like something that should really be added to the hardware guide as a warning.

And I wonder what is at fault? The controller itself? FreeBSD?

 

[cobrakiller58]

I have been using a pair of Transcend TS32GSSD370S for over a year with zero Issues on FreeNAS 11.0u4. It appears to be an upgraded version of the SSD370 series using the same controller with different memory.