[Slow read speeds from the array]

Hi all,

 

I'm a new Unraid user and i'm very happy so far, except of my reading speed from the array. I did a lot of tests and I'm very confused about the transfer rates.

That's the Situation:

- 5 Seagate 4TB HDDS (2 Parity).

- 2 Samsung 256GB Cache Disks

- 2x1 Gigabit Link Aggragation Network

 

- The best reading transfer rate from the array is around 50 MB/s. Small file have 35MB/s. Large files 50MB/s

 

From Cache Disk full 100 MB/s.

 

 

I expected also 100 MB/s from the array. 

- diskspeed.sh, version 2.6.4 came to the following result:

/dev/sdb (Cache): 565 MB/sec avg
/dev/sdc (Cache 2): 565 MB/sec avg
/dev/sdd (Disk 1): 163 MB/sec avg
/dev/sde (Disk 2): 152 MB/sec avg
/dev/sdf (Disk 3): 163 MB/sec avg
/dev/sdg (Parity): 152 MB/sec avg
/dev/sdh (Parity 2): 149 MB/sec avg
 

Now it's getting more weird. I made a CrystalDiskMark via mounted Network Volume (no cached share) and the results seems to be okay.

So there shouldn't be a transfer issue with my harddrives. But where is the bottleneck?

It can't be the Samba protocol or the network, because my cache disk is very fast via samba network. (FTP has the same transfer rates).

 

Why do I have just a maximum of 50MB's transfer speed instead of 100?

 

Please find the attached screenshots.

I hope someone has an explanation. Thanks for your help and sorry for my bad english.