Why does my HDD RAID0 seem faster than my SSD RAID0?

[Snacko]

I just added a 1T M.2 ssd to my system and was trying to compare speeds of all of my drives to see which I should use for boot/Windows and which I should use for games? I haven't looked at my drive setup in a few years since I built this system. And I forget whatever I learned when I did that.

I have:

• 2x SSDs in RAID 0
• 2x WD 10k rpm Raptors in RAID 0
• M.2
• RamDrive (just for comparison)

From what I remember, you need to look at Transfer Rates and Access Speeds for the average size files I will mostly be using. Looking at one of my primary games(DCS), it's largest size folder have average file sizes from 2mb to 8mb.

What seems weird is that my 2x HDD WD Raptors seem to be kicking everything else's butt!!???

Can anyone explain what I am seeing and what exactly I should be looking for to get the best performance? Is there a guide on the net somewhere that explains this and what tools to use to eval your system?

Please See my chart below.
And Thanks ahead!

 

[arestavo]

Try larger file sizes.

Also, I'm assuming that you're using a discrete RAID card and not the built in motherboard RAID for your Raptors? Nicer discrete RAID cards have built in RAM that acts as a buffer (think RAM disk that you don't have read write access to).

For games, any quality solid state drive of any type of interface (m.2, u.2, SATA III, PCIE) is best for games - doubly so for games with many small files that have to be loaded (like Skyrim and Fallout 4).

I've always kept my game drive seperate from my boot drive, but that is merely preference. Again, a quality solid state drive will be best as a boot drive. The difference between a quality SATA III SSD and the fastest NVME drive available with be minimal at best (I've tested a Samsung 850 EVO SATA III drive vs a Samsung 950 Pro NVME vs an Intel 900P PCIE - once you get a quality SATA III SSD the differences are very minimal unless you're prone to filling up your SSD past 80% which can have highly adverse speed reductions - then a larger capacity SSD will be better).

As an aside, unless you require high transfer speeds for work such as video editing, "RAID" zeroing your solid state drives only adds latency and doesn't load games/windows any faster than a single solid state drive will - and can often increase load times instead of decreasing them.

 

[drescherjm]

You are not getting 1GB / s (or even 1/2 that) from the 2 drive raid 0 raptors. This has to be some cache effect.

 

[drescherjm]

Nicer discrete RAID cards have built in RAM that acts as a buffer

Most don't have this much bandwidth. I think the cache is OS RAM cache on windows.

 

[extide]

You are not getting 1GB / s (or even 1/2 that) from the 2 drive raid 0 raptors. This has to be some cache effect.

Yeah some of those raptor benchmarks are showing 13+GB/sec -- there is definitely something up here.

I agree, try a larger file size because those numbers just arent realistic.

 

[drescherjm]

Repeat the test with the filesize being several GB instead of 256MB.

 

[Slash3]

Man, maybe I should dig my old Raptors out of storage again!

 

[likeman]

I just added a 1T M.2 ssd to my system and was trying to compare speeds of all of my drives to see which I should use for boot/Windows and which I should use for games? I haven't looked at my drive setup in a few years since I built this system. And I forget whatever I learned when I did that.

I have:

• 2x SSDs in RAID 0
• 2x WD 10k rpm Raptors in RAID 0
• M.2
• RamDrive (just for comparison)

From what I remember, you need to look at Transfer Rates and Access Speeds for the average size files I will mostly be using. Looking at one of my primary games(DCS), it's largest size folder have average file sizes from 2mb to 8mb.

What seems weird is that my 2x HDD WD Raptors seem to be kicking everything else's butt!!???

Can anyone explain what I am seeing and what exactly I should be looking for to get the best performance? Is there a guide on the net somewhere that explains this and what tools to use to eval your system?

Please See my chart below.
And Thanks ahead!

really should not bother with RAID once you have m.2 NVME in the mix ,, just use a size NVME SSD you need (like 1TB if that's enough space for OS and games typically) and a large HDD for storage (like WD Red 4-8TB) the samsung EVO you have is many times faster than a HDD (no matter how much you RAID it) one Normal none raided SSD is faster than a RAID HDDs

benchmarking and peak sequential speeds don't mean everything,, but SSD sequential and especially random is far faster than a HDD, once you move onto NVME SSDs your talking over 1-3GB/s and access latencies many times lower than a SSD

that said

your raid 0 HDD raptors don't seem to be right (well they are but due to test size), as 10-12GB/s speeds is just the DMI limit (assuming its intel mobo), somehow your testing the motherboard bandwidth limit (if you compare it to the ram disk to the RAID HDDs you see your not testing the disks your testing the cache of the RAID array not the disks themselves)

when doing the raid SSDs, the results you got are the expected speeds that you should be getting (the NVME SSD results are little low but to be expected on how it was tested)