draid read/write performance

[Yorick]

I was curious how draid compared to raidz when it comes to in-service read/write performance, not just rebuild performance.

I haven't found an article on that, and would love a link. I did find this slide: https://sc18.supercomputing.org/proceedings/tech_poster/poster_files/post185s2-file2.pdf

That shows, for a small draid (comparable to one raidz vdev), slightly better performance when pool is empty, and considerably less degradation as pool fills.

For larger draids, they outperform a multiple-raidz pool in every day use as well as rebuild, by the figures on that slide.

If you have something a little more substantial, please share! :)

 

[TrumanHW]

I was curious how dRAID compared to RAIDz in real-world R/W performance (vs. just rebuild performance).
I've found an article on that, and would love a link. I did find this slide: https://sc18.supercomputing.org/proceedings/tech_poster/poster_files/post185s2-file2.pdf

....
If you have something a little more substantial, please share! :)

This article is no exception to your experiences (it's the dRAID man page, which I wrote the author about).
https://openzfs.github.io/openzfs-docs/Basic Concepts/dRAID Howto.html

That said, I'd be happy actually to clear up a ZFS array I was using temporarily to perform some tests...
Presently I'd used it to copy off all data from a RAIDz2 array which had 75% of written content written with dedup enabled!!. lol

Which, as an aside, I think it'd be wise for the dedup man page to address the known scenarios in which it's beneficial:
You host VMs which are either homogenous OS version or many versions which are homogenous ... with expensive (fast) storage.
Your backups system is great? But can't do incremental or differential ..?
(honestly, having heard few beneficial scenarios aside from many VMs using expensive (flash) media or SANs, such examples seem easily listed.)


Would an 8-Drive dRAID doing synthetic testing be of any use..?
That of course is assuming it's available for ZoL ... yes..?

 

[Sawtaytoes]

Now that this is in Cobia and that 3 years have passed, I made a new thread here because I specifically wanna look at RAID-Z (multiple vdev) vs dRAID performance in throughput and IOPS:

Should I be making multiple dRAID vdevs?

I keep hearing that dRAID is there for 100+ drive pools, and looking at TrueNAS SCALE Cobia, the UI is clearly designed around a single dRAID vdev. It doesn't even let you add more dRAID vdevs. So I'm wondering if dRAID is this mystical "one vdev is plenty" scenario. Does it work that different...

www.truenas.com