cancel
Showing results for 
Search instead for 
Did you mean: 
Nico19
New member
2 1 0 0
Message 1 of 3
299
Flag Post

Raid 0 with 2 SSD's perform worst now than a single setup.

HP Recommended
Z620
Microsoft Windows 10 (64-bit)

I setup the Z620 wit 2 x 860 EVos 250GB SSD's about 1 year ago and during our initial testing wit different strip sizes and bench marking I found a rraid 0 in the intel sata bridge with a block size of 16kb to be the most balanced setup and I got about 900 - 1000 seq. read and a bit more write speeds. 

 

I recently run the the benchmark again and speeds are now around 450mb/s in raid 0 so I lost almost 50% performance. Also it seems the raid 0 is performing slower than a single SSD. 

 

Had a support ticket open, nice guys but this got no solutions. 

 

HPZ620 dual xeon setup 48GB 

all the drivers are up to date incl. firmware and  bios incl. intel enterprise storage controller. 

bios is set to raid + ahci 

 

I'm checking today that both SSD are hooked up to the 6gb/s ports but quite sure this was never changed from the initial setup  Just one day a W10 reboot and performance went down. I'm testing the SSD today but since I have acronis backups I changed to s single ssd config and speed is well over 500+ 

 

Nico Albrecht
2 REPLIES 2
DGroves
Level 11
4,696 4,670 442 993
Message 2 of 3
Flag Post
HP Recommended

raid-0 on the z620/z820 systems using the onboard SATA 6/3 controller is rather pointless as most single mid to high end ssd's are able to saturate the SATA bus in a single drive setup, in simple terms this means that a single SSD is able to xfer data as fast or faster than the bus can transfer data your 900 - 1000 seq R/W speeds is from the drives onboard Cache, and is not the  real sustained speeds of the system when the cache is filled and the 620/820 only have two SATA 6GBps ports, the others are 3Gbps (yes i know the 820 has a LSI controller that can do 6GBps for SAS and 3GBps for SATA)

 

Read this link about the bandwidth throughput, which is supported by the interface

 

https://kb.sandisk.com/app/answers/detail/a_id/8142/~/difference-between-sata-i%2C-sata-ii-and-sata-...

 

if your looking for more speed then a PCI-E based SAS/SATA  Raid controller is required, and even these are bottlenecked due to the PCI-E 3.0 bus used on these "z" workstations when using 4 or more SSD's with most raid controllers (there are exceptions but these controllers are very expensive)

 

i've tested PCI-E x2 Raid/SATA cards and high end SAS/SATA raid cards along with mods for booting from a nvme SSD

and the overall best solution for most users is the nvme boot mod as it gives the speed along with lowest cost overall

Was this reply helpful? Yes No
Nico19
Author
New member
2 1 0 0
Message 3 of 3
Flag Post
HP Recommended

Good answer and since the HP support couldn't help I had a good look at the diagram this morning of all the sata ports again and noticed that one SSD was hooked up to a 3GB sta port. 

 

Now both SSD's are on 6GB ports and read is around 975mb/s and write at 1050mb/s . Those values can be maintained even over very long file sizes e.g 64GB with random data where caching wouldn't work anymore, values are much higher on 1GB sizes but happy now.  Not chasing the mbs here. Not sure why the 2nd SSD was hooked up but it is back at expected raid 0 speeds.  I send the block diagram to HP and they should have spotted that but hey. 

Nico Albrecht
Was this reply helpful? Yes No
Warning Be alert for scammers posting fake support phone numbers and/or email addresses on the community. If you think you have received a fake HP Support message, please report it to us by clicking on "Flag Post".
† The opinions expressed above are the personal opinions of the authors, not of HP. By using this site, you accept the Terms of Use and Rules of Participation