Parity Drive size and speed issue


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9 minutes ago, trurl said:

Why does it say disk2 is btrfs when all of your other array disks are xfs? Is that even correct? Default for array disks is XFS so you would have had to intentionally change it if that disk really is supposed to be btrfs.

I have Disk 2 back online now.  as far as btrfs vs xfs not sure why.. I do not remember changing anything when setting up it.  once I get parity back I plan to remove disk 2 and disk 3..  I have a 4tb and 6tb on deck to replace them  Parity sync is still extremely slow and the size mismatch is still present... Thank you for your replies!  I appreciate any help!1015294551_ScreenShot2022-03-11at9_45_25AM.thumb.png.1beef6de934edd5b72515547a14f4862.png

Edited by Thitt0927
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A lot of dumps in your syslog, seems related to disks. Maybe a controller issue?

 

4 minutes ago, Thitt0927 said:

once I get parity back I plan to remove disk 2 and disk 3

Since these have little or no data on them, you could just New Config and build parity without them.

 

You seem to have a lot of disks for someone just starting, and since some are small, I am guessing some are not new. Do any have SMART warnings on the Dashboard page?

 

I think I would just remove those small disks also. Each additional disk is an additional point of failure, and they aren't adding much.

 

Not sure about parity size, maybe it isn't upsized until rebuild is complete.

 

Your appdata and system shares are on the array. You want these all on one of your fast pools and set to stay there so your docker/VM performance won't be impacted by slower parity array and so your array disks can spin down since these shares always have open files.

 

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4 minutes ago, trurl said:

 

5 minutes ago, trurl said:

You seem to have a lot of disks for someone just starting, and since some are small, I am guessing some are not new. Do any have SMART warnings on the Dashboard page?

I started a messing unraid a few months ago.  everything was running with no issues so I had been adding disks.  I started wanting to get disks larger than my 4tb parity thats when I decided to replace it with an 8tb today and when issues started.   there are no SMART warnings on the dashboard.   

 

 

 

 

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nobody answered the initial question "why is Parity still using 4Tb only?" yet, so I try to add my explanation:

 

The Parity drive must be the largest in the array because it stores the addes sums of all sector data of the data disk. Initially it is fully wiped out with zeros, then the "parity regeneration" task will start and it will read every sector of the data disks, sum those up and store the result on the parity disk.

If a data disk is smaller than the current position, it is skipped for this reading.

At the end, all sectors of the parity drive that have a correspondinf sector of a data drive, will be used, the remaining sectors are untouched and still show zeros.

So if you largest data disk now is only 4 tb the parity drive also will only be used up to this point, 4Tb.

 

But the reason for this ("the parity drive needs to be the largest disk in the array") is that now you can add new disks or exchange old one with disks up to 8 Tb in size.

 

So, its like an investment into the future, it will then safe you a lot of time (no need to regenerate everything, just refill the new disk up to the size of the old one or just add a new empty drive instantly)

 

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Just now, JorgeB said:

Good news is that the crashing is gone, how is the speed?

 

Pool issues are the result of a duplicate filesystem on the unassigned disk (sdl), I guess that's old parity? Wiping/reformatting/disconnecting it should fix that, after rebooting.

speed is still pretty slow sitting around 38-40 mb/s I assume it should be a bit faster than that.

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T

4 minutes ago, Michael Meiszl said:

nobody answered the initial question "why is Parity still using 4Tb only?" yet, so I try to add my explanation:

 

The Parity drive must be the largest in the array because it stores the addes sums of all sector data of the data disk. Initially it is fully wiped out with zeros, then the "parity regeneration" task will start and it will read every sector of the data disks, sum those up and store the result on the parity disk.

If a data disk is smaller than the current position, it is skipped for this reading.

At the end, all sectors of the parity drive that have a correspondinf sector of a data drive, will be used, the remaining sectors are untouched and still show zeros.

So if you largest data disk now is only 4 tb the parity drive also will only be used up to this point, 4Tb.

 

But the reason for this ("the parity drive needs to be the largest disk in the array") is that now you can add new disks or exchange old one with disks up to 8 Tb in size.

 

So, its like an investment into the future, it will then safe you a lot of time (no need to regenerate everything, just refill the new disk up to the size of the old one or just add a new empty drive instantly)

 

Thank you.. so if i am understanding this correctly since the original parity was 4tb that is what it is rebuilding onto the new 8tb drive and i should not worry that the sync shows 4tb 

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7 minutes ago, JorgeB said:

duplicate filesystem on the unassigned disk (sdl), I guess that's old parity?

No, it's a duplicate of disk2, so after wiping it there might still be issues with parity because there's only one btrfs array disk, likely also the reason parity is only showing 4TB, post new diags after fixing sdl and rebooting.

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  • Solution
1 hour ago, trurl said:

Since these have little or no data on them, you could just New Config and build parity without them.

 

You seem to have a lot of disks for someone just starting, and since some are small, I am guessing some are not new. Do any have SMART warnings on the Dashboard page?

 

I think I would just remove those small disks also. Each additional disk is an additional point of failure, and they aren't adding much.

You can stop the current parity build, then go to New Config and create a new array without those disks and rebuild parity.

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9 minutes ago, trurl said:

You can stop the current parity build, then go to New Config and create a new array without those disks and rebuild parity.

This may sound like my best course of action.. couple questions.. how do I start a new config? did not seem obvious to me.  Will it keep all my docker settings? 

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1 hour ago, trurl said:

New Config only allows you to reset disk assignments, doesn't change anything else about your settings.

 

https://wiki.unraid.net/Manual/Tools#New_Config

Thank you this is solved all my original issues parity sync is running at 130 mb/s and shows the correct size...the issue i have now is once i did the new config one my my drives is showing unmountable/ wrong or no file system.  any insight on that?  Again thank you for solving the other issues1775479318_ScreenShot2022-03-11at1_49_06PM.thumb.png.fc7729882faa45d3d9555a641cde69dc.png

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