disc full?

o0o

Dabbler
Joined
Feb 10, 2021
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20
Hi,

I have a stripe pool with JBO_myold_Ds. Five discs with different sizes. (I understand the nosense in that, but that's not the topic here.)
In the moment I am writing data on this pool. The smallest disc shows "some" activity, but only minimal transfer rates. Before the data transfer appeared to be equal regarding to the speed of the single discs. Does it look like this, when the disc is full? See attachment.
 

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sretalla

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Does it look like this, when the disc is full?
Not necessarily.

You can have a look at zpool list -v to understand the data distribution as it stands.

ZFS will decide on its own how data will be written to the various VDEVs based on the transaction group size and available (contiguous) space on the VDEVS.

If a pool is created new with all VDEVs present at the beginning, the writes should be more-or-less spread evenly. If you add VDEVs as you go, it can be all kinds of unpredictable as to where the next write will go. (unequally sized VDEVs conform to this second case from the start too)
 
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o0o

Dabbler
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Feb 10, 2021
Messages
20
Thanks for your reply! That code helped. This very disc is full. CAP 99%, 4.6GB of 460GB free.
I created the pool with all VDEVs at the same time. For days all was as expected, activity and spreading the data was (quite) equally. Yesterday it changed.
Great help, thanks.
 

joeschmuck

Old Man
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I have a stripe pool with JBO_myold_Ds. Five discs with different sizes. (I understand the nosense in that, but that's not the topic here.)
I love the way you acknowledge that you do not have the best drive setup, it's good becasue we get some folks here who will defend a bad decision to their dying breath. I've done some not so great setups myself as well but in time (generally after data loss) I do it better the next time around.
 
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