Studio XPS 9100, latency

What OS are you using?  This program is invalid for Win 10.  

Use the Resplendence Latency Mon program instead.  

https://www.resplendence.com/latencymon

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@NinjaUnmatched wrote:

1. When I run a single SSD in AHCI mode it runs fine

2. but if I try to go RAID 0 with 2 SSDs I get a lot of system latency.

 

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1. Good. Is the XPS-9100 SATA-2/300 or SATA-3/600 ?

2. Then don't.

Why would you even want RAID0? With RAID0, if one drive fails, you lose everything because neither drive has a complete copy of any file. 

Is this an attempt to speed up drive access?  Or, if you're just trying to back up one drive on the other one, you'd want RAID1 not RAID0.

The purpose is for a drive speed improvement. I know what striping is. I will just use backups...  Just not sure why there would be that much latency on the system.  In a game like Overwatch you can hear the audio distortion every 3 to 4 secs.  

Best option is to just use one disc/SSD and do regular full drive (all partitions) backups with a program such as Macrium Reflect.

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@NinjaUnmatched wrote:

The purpose is for a drive speed improvement. 

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Had same issue with an even older X58 system - limited to SATA II, ~300 MB/s speeds.  Dismissed a SATA III, ~600 MB/s PCIe card solution as too old.  Jumped over SATA and went straight to a M.2 NVMe SSD in a M.2 NVMe to PCIe adapter card.  Getting ~1700 MB/s.  And, bootable if you use an older Samsung 950 PRO.

I tend to doubt RAID0 would give you any significant speed improvements with SSDs, since it was designed to speed up access to slow hard drives. Are there any real life tests on the net showing if and how much RAID0 might speed up 2 SSDs?

Don't know why you see that latency with RAID0. Do you have the most recent BIOS, chipsets and other drivers installed on this PC? Don't know if that would make any difference - or not. But update as you think necessary, keeping mind there's always a risk that a BIOS update might brick the motherboard.

Or just do without RAID0...

EDIT: @Techgee types faster than I do... :Smile:

BTW: A recent windows update was causing performance and audio issues in games running under Win 10. Microsoft advised removing that update and supposedly released a new version that didn't cause the problem. Read my thread here, and if you still have update KB4482887 installed, set a System Restore point and then uninstall it. See if that helps...

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@NinjaUnmatched wrote:

In a game like Overwatch you can hear the audio distortion every 3 to 4 secs.  

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Ah...  That symptom helps pinpoint it.  Experienced it myself on a different X58 Dell system.

The latency is a known issue introduced with Intel RST RAID drivers in Windows 10 starting with version 1803 April 2018 Update on certain X58 chipset systems.  See here where issue occurs both with a Dell Studio XPS 9100 and a Dell Studio XPS 435MT.

Workaround is to:

1. not use RAID mode (for example, set BIOS to AHCI mode instead), or
2. install older Intel RST drivers. 

See my recent Dell Forum post on driver versions that seem to work here.  Scroll down to last two paragraphs of section bold-titled "Mouse/Audio Stutter Workaround" for working Intel RST versions and links.  The same Intel RST drivers apply to the Studio XPS 9100.

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@RoHe wrote:

1. I tend to doubt RAID0 would give you any significant speed improvements with SSDs,

2. since it was designed to speed up access to slow hard drives.

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1. Agreed

2. Therefore the latency is introduced because you are using disks much faster than the RAID controller was ever meant to handle in a RAID-0.

Wow the responses so far are useful... Just give me the weekend to try out the solutions and I'll let you know how it goes.

The last one about being faster than the MB controller makes sense also but I will try out solutions first because I know Windows 10 does introduce issues at times when you game for some people.

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@RoHe wrote:

I tend to doubt RAID0 would give you any significant speed improvements with SSDs [...]. Are there any real life tests on the net showing if and how much RAID0 might speed up 2 SSDs?

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With caveats, RAID 0 does almost double sequential performance - regardless of whether array is HDs or SSDs and whether drives are SATA II, III or NVMe.  Copying large video and photo files (which are mostly sequential operations) will be faster.

BUT, while sequential or large file performance is almost doubled,  small file (4K) random IOPS performance usually takes some kind of hit and is reduced.  Each disk operation must be synchronized to get data to/from both drives, resulting in always waiting on whichever drive is slower in carrying out the disk I/O (plus there's also RAID controller overhead).  End result is RAID 0 will appear "less snappy" than a single drive of the same type.

You can find performance numbers for SSDs in RAID 0 for SATA II, III and NVMe on the net.  Pretty much what I mentioned above.

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@RoHe wrote:

Don't know why you see that latency with RAID0. 

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You wouldn't - unless something's wrong.  And, especially not intermittent latencies, as is the case here.

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@Tesla1856 wrote:

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2. Therefore the latency is introduced because you are using disks much faster than the RAID controller was ever meant to handle in a RAID-0.

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RAID controllers are designed to perform up to full throughput of the interface (SATA II at 300 MB/s in this case) times the number disks supported in an array (I believe only RAID 0 and RAID 1 is supported on the 9100 native controller - so, x2).  The 9100 should see sequential file rates with 2 SSDs in RAID 0 of about 540 MB/s (2 x SATA II actual of about 270 MB/s), less controller overhead which would probably bring it down to around 500 MB/s.

SATA II RAID 0 benchmark here.  Another one here.

Man... choking the heck out of the drive...haha.   But your solution worked I take  it...   no latency? 

My faith in the board itself though is diminishing now that I've actually took the time to review it's specs.  Depending on cost I may roll with another board. The price for some of controller cards is near the price of an eBay Asus board with better memory support idk still deciding. 

I've been down this decision rabbit hole before - how to get better disk performance on a native SATA II system with PCIe 2?  Considered a SATA III card, but ended up going with a M.2 NVMe SSD via PCIe to M.2 NVMe adapter card.  The 1700 MB/s I got over the native SATA II's 270 MB/s was worth the effort.  Bought a used Samsung 950 PRO as it's one of the only NVMe SSD that's really bootable with non-UEFI systems like the 9100.

The PCIe x8 slot in the 9100 should be 2.0.