transfert rate between disks shares : what to expect ?

[RNO]

Hello every one.

I am using unraid for a while now.

I have a pro licence on a 24 bays server with  1 parity drive

my brand new parity drive is a 10TB Toshiba Enterprise Capacity https://static.digitecgalaxus.ch/Files/1/4/3/7/9/5/3/8/eHDD-MG06ACAxxx-Product_Overview.pdf

I chose it to replace a Western Red of 8TB, expecting some improvement in speed and reliability.

Getting a new parity drive allows me to use the previous one as Data in place of a smaller disk.

So... I am moving files, in term of TB.

I usually connect to the server using putty, launch Midnight Commander and browse the disk mounts to find the rights files to move between disks.

 

But it takes forever, and I am a bit disappointed, each time, that the transfer rate is not more than 20MB/s.

I am moving files inside the server, from one disk to another, so why is it so slow ?

 

When i add files to a share from my windows computer, going through my GB network, the transfer rate goes from 60MB/s to 150MB/s, depending on the file size and the fragmentation of the file (I suppose, I don't really know how this filesystem works).

 

So why is it so slow internally ?

Edited January 18, 2019 by RNO

[JonathanM]

Moving data between array disks causes writes on 2 different data disks, which means the parity disk is cycling back and forth between the two write areas. It's going to be slow.

 

Normally you would not need to move files from disk to disk, as each disk can participate in user shares which hides the specific disk being accessed. When you fill a disk, let that disk stay full, and allow all the new files to go to the new disk. Empty disks are faster to write to, and for a typical media use case, the older full disks are read less often, while the new content is accessed more frequently.

 

If you insist on balancing things out manually to satisfy some internal organizational OCD, you will find that both the balancing process and subsequent usage are slower than they could have been.

 

Disclaimer: I factually KNOW all this stuff to be true, but I can't help myself, I move stuff from disk to disk to keep things organized to my liking. When I move things, I use tools that don't need to be watched, and let the process run its course in my absence. If I'm not there to watch it, it doesn't matter to me whether the move takes 5 minutes or 5 hours.

[RNO]

Thank you for your input !

I tried to just copy files from one disk to the other and it didn't change the speed much.

I understand that moving manually files around can be seen as an OCD.

I tend to prefer to isolate data depending on a criteria. 

This allows me to know exactly where is the file, to have only one drive up if I am only using those data, and to handle available space perfectly.

I tried the other way first but was pretty much unpleased with it, so I came back to this OCD.

But I do understand the paradox.

 

To manage this kind of task, I use MC and let it go for as long as necessary, but the amount of DATA is tremendous and the rate is unbearable.

I was wondering if I was doing it wrong.

I am going to reflect on this for a while...

[ZataH]

Have you tried to enable turbo write?

Sendt fra min ONEPLUS A6003 med Tapatalk

[RNO]

What is turbo-write ?

[trurl]

3 minutes ago, RNO said:

What is turbo-write ?