Generally how long does a parity sync last?

[Victor90]

Hi. Started my first array ever. I've added a 8TB parity drive, another 8TB and 6TB drives for the array and a 512GB SSD for cache.

 

Currently my first time parity sync on empty drives (or well, they for some reason each have ~50gb worth of data on them for no known reason to me? Why do they have some data if unraid formatted them after they were added to the array?) is running for the past 2 hours and unraid estimates it'll keep running for next 10 hours. Why is it this long and is it always this long? Write speeds are ~170 megs per sec.

 

Is this normal? Does this mean my next parity sync once I add all my existing data (~9TBs worth of data) will take like 7 days?

Edited September 2, 2022 by Victor90

[tjb_altf4]

1 hour ago, Victor90 said:

for some reason each have ~50gb worth of data on them for no known reason to me?

I'm assuming its been formatted with XFS, this is an overhead for the filesystem.

 

1 hour ago, Victor90 said:

Currently my first time parity sync on empty drives is running for the past 2 hours and unraid estimates it'll keep running for next 10 hours. Why is it this long and is it always this long? Write speeds are ~170 megs per sec.

That's a fairly normal speed for parity, it will go up and down at various stages of the check.

For comparison my array made up of 10TB drives takes about 20hrs to check parity.

 

1 hour ago, Victor90 said:

Does this mean my next parity sync once I add all my existing data (~9TBs worth of data) will take like 7 days?

The time for parity checking is primarily impacted by the capacity of the largest disk in the array, whether the drives are full or empty makes no difference as the system is checking it all to verify parity is correct.

@SpaceInvaderOne has a great video explaining how parity works in Unraid if you'd like to learn more.

 

[kizer]

11 hours ago, Victor90 said:

Is this normal? Does this mean my next parity sync once I add all my existing data (~9TBs worth of data) will take like 7 days?

 

Honestly your numbers seem pretty much on par with what is considered Normal. I've come to the conclusion that things moving on unraid simply take as long as they need to take when your numbers seem normal. 

 

No because your parity will be syncing at the same time your adding data. However when you run your Next Parity check Id guess since my system takes 9hours on my 4TB Parity that yours would probably take close to 15-20hours with your 8TB drive.  I personally have my Parity check set to run on the first of the month at 12AM. So when I'm sleeping it does its thing. 

 

 

[CablDeViL]

I just did my first install. 14tb parity and 60tb formatted array.  26 hours. FYI ymmv

 

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