unRaid Parity Check duration

[PlyLean]

So I have an unRaid Server that I use as
a) a general-purpose NAS 
b) to stream Media using Plex
and c) to play around with VMs, Containers and so on.

It's an i5-2400 based system (that I found for cheap on eBay) with  5TB + 1TB HDDs for storage, another 5TB HDD as parity drive plus an old 128GB SSD as a cache drive.

 

It runs a weeky Parity check that usually takes between 8h and 8,5h to complete (see attatched picture).

 

So now the actual question: Is this a normal time for a check like that?
If it is: How do people/firms with even more storage (like LMGs Petabyte Project) handle these checks? Wouldn't they take forever to complete?

If it's not: What can I optimize?

[Electronics Wizardy]

That time seems fine.

 

Large storage arrays don't use a parity system like this, and its all done in real time. Its also based off the speed of the slowest drive normally, so adding more drives won't make it slower, as all drives are read at once.

 

 

[beyonddc]

You are fine.  The larger your parity drive is or the more drives you have in your array, the longer it will take to calculate the parity.  That's just the nature of it.

 

 

My Unraid array consists of

1 x 10TB parity drive

2 x 8TB in the array

3 x 3TB in the array

 

240GB SSD as cache but that's out of the parity check equation.  Parity check doesn't care your cache drive.

[porina]

I have 6x3TB drives (4 data, 2 parity) and that takes around 7 hours. I'm not CPU limited (yet?) and think the time is mostly due to the transfer speed of the drives.

 

Also I wouldn't worry too much about these parity checks. Last one I ran was about 6 months ago. Never had an error with previous scans.