Reading other disks when writing to disk

[chazman88]

I have an ubuntu VM that sporadically writes huge amounts of data directly to a user share (no cache drive). When this VM is writing data to the share the same VM struggles massivley in reading data from the share at the same time.

The transfer from the VM to the share appears to settle around 120MB/s-130MB/s which (i think?) is perfectly reasonsable, but ive noticed that when the share is being written to there is always an equal "MB/s" "Read" happening from other drives, sometimes all the drives are reading at the same speed sometimes just a select few drives (see attached screenshot).

 

Is this normal?

Is there anyway I can improve the ability for the VM to read from the share/array whilst is it also writing to it?

 

Hopefully this all makes sense!

Thanks

 

[ChatNoir]

I could be wrong, but that looks like a normal behavior if you have reconstruct write activated.

It is under Settings / Disk Settings or can be adjusted on the fly by the plugin Auto Turbo Write Mode

[chazman88]

Thanks,

 

reconstruct write is whats also known as turbo write?

If i disabled this and went to auto or read/modify/write would this increase the ability for the disks to be read from whilst also being written to?

[ChatNoir]

54 minutes ago, chazman88 said:

reconstruct write is whats also known as turbo write?

Yes.

54 minutes ago, chazman88 said:

If i disabled this and went to auto or read/modify/write would this increase the ability for the disks to be read from whilst also being written to?

As far as I understand, no.

It is supposed to increase write speed to an Array drive at the 'cost' of reading and possibly waking up additional drives.