Storage Spaces Low Performance

[LIGISTX]

I know this has been asked many times in some way shape or form, but I am looking to understand why standard (should be a striped array) storage spaces of SSD's results in single SSD performance.

 

I have 2 missmatched drives, but both 1 TB, for fun I figured I would set up storage spaces to speed up my photo library assuming it would act as RAID 0 and thus theoretically give me 80-90% more performance than a single drive, and I get, maybe 10% at best improvements if any at all. I saw a max read speed of 550 MB/s.

 

Any ideas why this would be? I am not entirely sure if RAID 0 SSD's would even make lightroom load images faster, but I figure I have the drives and I don't need any redundency here since all data is also stored on my ZFS truenas array...

 

@Electronics Wizardy im sure you will have some suggestions. Watched your video on parity, but not sure if the same tips are applicable to simple (stripe) arrays. 

[Eigenvektor]

Can you provide some info about the hardware?

 

550 MB/s makes me assume those are SATA 3 drives. Most likely explanation: You've reached the maximum throughput of the SATA controller.

[LIGISTX]

1 hour ago, Eigenvektor said:

Can you provide some info about the hardware?

 

550 MB/s makes me assume those are SATA 3 drives. Most likely explanation: You've reached the maximum throughput of the SATA controller.

Oh, hmm. Is a SATA controller wired for all of its ports to be capable of SATA 6 speeds across all drives, not just per drive? 
 

Hardware is an Asus z790 mobo. 

 

Looking into it further, it does look like it should be per port, not per controller. So I should be able to get 2x that speed assuming 100% scalling which I do not expect. But I would expect at lesat 70-80%....

[leadeater]

7 hours ago, LIGISTX said:

@Electronics Wizardy im sure you will have some suggestions. Watched your video on parity, but not sure if the same tips are applicable to simple (stripe) arrays. 

It matters for any type, the reason is if there is no I/O translation required then multiple of the storage abstraction layers are skipped vastly improving performance.

 

The default Interleave size is 256KB so for a 2 disk Simple Virtual Disk format the partition with a 512KB Allocation Unit Size.

[leadeater]

2x SSD (VHDX's living on 2 different SSDs) using Windows 10 GUI all defaults and Simple type selected.

 

 

Format existing partition/virtual disk to 512KB AUS

 

[LIGISTX]

4 hours ago, leadeater said:

2x SSD (VHDX's living on 2 different SSDs) using Windows 10 GUI all defaults and Simple type selected.

 

 

Format existing partition/virtual disk to 512KB AUS

 

Well that looks promising. 
 

So all I do is format the existing array with 512kb? I’ll give it a shot after work today, thanks!

[leadeater]

18 hours ago, LIGISTX said:

Well that looks promising. 
 

So all I do is format the existing array with 512kb? I’ll give it a shot after work today, thanks!

Did you manage to give it a try?

[LIGISTX]

5 hours ago, leadeater said:

Did you manage to give it a try?

I did, it didn’t seem to make any difference. But all I did was format the drives vis disk manager or whatever it’s called. I may try and redo the setup from scratch when I have more time, only had a few minutes yesterday. 
 

But, a buddy of mine needs a few SATA SSD’s, one for Proxmox VM expansion and one for desktop, so I think I may solve both first world problems by selling him both my drives at a deal, and just getting myself an additional nvme drive. It’s not worth 70 bucks on its own, but if I can bring that cost way down, suddenly I am more willing to do it even tho I definitely don’t need that performance just for Lightroom photo’s. 

[leadeater]

3 hours ago, LIGISTX said:

But all I did was format the drives vis disk manager or whatever it’s called

Yep that's it, just format there with 512KB selected for AUS. It's probably application/use case related for why you're not getting a big speed up. 

 

Getting an NVMe as you intend is the far better option.

 

You could mess around in PowerShell creating a new Virtual Disk in there with a smaller Interleave value and then format the partition accordingly (2x Interleave size for you) but no point unless you stick with your 2 SATA SSDs.

[LIGISTX]

14 minutes ago, leadeater said:

Yep that's it, just format there with 512KB selected for AUS. It's probably application/use case related for why you're not getting a big speed up. 

 

Getting an NVMe as you intend is the far better option.

 

You could mess around in PowerShell creating a new Virtual Disk in there with a smaller Interleave value and then format the partition accordingly (2x Interleave size for you) but no point unless you stick with your 2 SATA SSDs.

Ya, it’s strange. I did that, and then copied ~400GB of raw images from my 990 pro to this array, and I only got about 560 MB/s, which is only slightly higher then what a single SSD would be able to do. Who knows, if my buddy ends up not wanting my SSD’s, I’ll deal with it more at that point.