Millions of Parity Reads and Writes without Parity Check


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Hello! Well the title says it all. I am having a very very peculiar issue where usually overnight but also sometimes throughout the day, something is continually reading and writing to the array (usually Disk2). Now this is sometimes a "common" problem with unraid. The part that is thrown me for a curve is that it is ALSO reading and writing an equivalent amount of data to the parity drive. No errors being corrected that I can see.


1) I have tried restarting docker which I thought fixed the problem for a couple days... but then it came back.

2) iotop was not useful given the intermittent issue

3) I tried disabling party check scheduler which again stopped the problem for a couple days I think but could be a coincidence

4) I disabled ALL docker containers which did nothing so I dont think it is a container writing that much.



Any help or guidance or direction is appreciated! I got to solve this before my drives go bust!

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1 hour ago, apandey said:

This sounds normal to me. Any writes to any disk in the array will need the corresponding part of parity to be recomputed and written. That is how parity works


See here -


1 hour ago, JorgeB said:

That's expected, anything written to an array disk will also be written to parity, and with default read/write/modify, parity is also read.

Thank you guys for the comments! I guess I was thrown by the parity reads matching the array disks. I have downloaded and set up the file activity plugin. I ran it so I guess I will just have to wait and see if it catches anything suspicious going on. I will report back once it happens again to see if it catches anything. Cheers!

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