XFS Drives high disk fragmentation

[Meller]

So I've read up on people running the following commands

xfs_db -r /dev/md# (where # = whichever disk you want to mount to inspect)

From there you can run "Frag" to see the fragmentation on the disk. 

I have 8 drives (7 drives 1 parity).  All are roughly 8TB.  The lowest one is 6.7TB used and the most full is 7.2TB.  When I ran a frag check, I was getting fragmentation at 97.5% on the least fragmented drive, with the highest being over 98%.  Most of the articles/reddit/forum posts I see have people talking about anything over say 60% is high enough to make them defrag.  Where as a lot of people are at like 40% or well under.

With mine being at 97-98%... is there any good way to defrag them all at once, rather than running this method one drive at a time?  I understand this can take many days to run, per disk.  Just curious what the best approach or method would be. 

[JorgeB]

43 minutes ago, Meller said:

is there any good way to defrag them all at once

Only if you disable parity, or it would be hammered and take much longer. 

[Meller]

Ok, if I didn't disable parity... how would I go about defragging them in the best method?  Is one at a time still the only route?

[JorgeB]

32 minutes ago, Meller said:

  Is one at a time still the only route?

With parity is what I would recommend.

 

 

[Meller]

Ok, if I disabled parity... how would I go about defragging them in the best method?  Is one at a time still the only route?

[JorgeB]

If you disable parity you can defrag them all the same time.

[John_M]

Have you see this thread?

 

 

Unless things have changed in the last five years, it hardly seems worth the effort. You might make better use of the time simply copying files sequentially from one disk to another. I personally think it's a non-issue anyway.

 

[Meller]

On 4/13/2021 at 6:47 AM, John_M said:

Have you see this thread?

 

 

Unless things have changed in the last five years, it hardly seems worth the effort. You might make better use of the time simply copying files sequentially from one disk to another. I personally think it's a non-issue anyway.

 

Strongly disagree. While yes, it took me a couple of weeks to defrag (xfs_fsr) 8x8tb drives all at 89% or higher capacity.  I can honestly say... once I finished and had all drives at 1% fragmentation or less... the speed was so much faster.  Files and folders open almost immediately, plex media plays almost immediately with the ability to  skip/search so SO much faster.

I will 100% keep an eye on my disk/file/folder fragmentation for now on as keeping it low has proven first hand how extremely beneficial it is in terms of speed.

[FlyingTexan]

How did you check how fragmented your drives were? While they were defragging were you still able to use them? I was hoping to find a disk utility docker or plugin but no luck. 

[ljm42]

On 2/4/2023 at 11:16 PM, FlyingTexan said:

How did you check how fragmented your drives were? While they were defragging were you still able to use them? I was hoping to find a disk utility docker or plugin but no luck. 

 

See the link John_M posted a few comments back