Doing a parity check, and have over 400+ million errors. Still ongoing.

[KimoB]

I replaced my parity drive a week ago (new 8TB drive) and did the parity swap procedure as one of my 4TB data drives was reporting errors.  (my old parity drive was 4TB)

 

The Parity copy, and subsequent parity check went fine, however when my next scheduled parity check started (sunday night), I am seeing the Sync errors corrected continuously counting up at over 400 million so far.  My parity check usually takes 14-15 hours (when the parity drive was 4TB), and it is currently 21 hours, and with 8-9 more hours to go.  I don't remember seeing any errors this morning (when it was below 50%, and I suspect the errors started right after the 50% mark, which makes me wonder if it is "correcting" the empty parts of my parity drive?  I believe the parity check is set to "not" correct errors since it is the automated run.

 

Adding my diagnostic file.

homeunraid-diagnostics-20230102-1755.zip

Edited January 3, 2023 by HomeUnraidServer

[itimpi]

There have been reports of the ‘extra’ space not always being correctly zeroed when upgrading the size of the parity drive (although the exact combination of circumstances to trigger this have not been identified as far as I know).  If the errors only start occurring after you get past the old size of the parity drive then you have almost certainly encountered this.  In such a case the only fix I know of is to run a correcting parity check after which subsequent checks will no longer report the errors.

[KimoB]

The parity finished, and what is interesting, is the pop up message indicated 0 errors, and that it only took 9 hours and 46 minutes (which is the usual time when I had a 4tb drive).  It certainly took more time than that.

 

Looking under the main section, this is the output:

 

Last check completed on Tue 03 Jan 2023 03:46:14 AM MST (today)
 Duration: 1 day, 6 hours, 46 minutes, 13 seconds. Average speed: 72.2 MB/s
 Finding 709671375 errors

 

This is my parity check rebuild history, and adding an updated diag file.  

 

Parity-Check2023-01-03, 03:46:14 (Tuesday)8 TB1 day, 6 hr, 46 min, 13 sec72.2 MB/s OK709671375

Data-Rebuild2022-12-27, 17:44:57 (Tuesday)4 TB9 hr, 46 min, 34 sec113.7 MB/s OK0

Parity-Check2022-12-26, 06:42:50 (Monday)4 TB9 hr, 42 min, 49 sec114.4 MB/s OK0

Parity-Check2022-12-23, 05:57:09 (Friday)4 TB9 hr, 43 min, 16 sec114.3 MB/s OK0

Parity-Check2022-12-22, 07:42:50 (Thursday)4 TB9 hr, 43 min, 18 sec114.3 MB/s OK0

Parity-Check2022-12-19, 06:43:09 (Monday)4 TB9 hr, 43 min, 8 sec114.3 MB/s OK0

 

I can certainly do another parity with write corrections enabled.

homeunraid-diagnostics-20230103-0415.zip

[itimpi]

25 minutes ago, HomeUnraidServer said:

I can certainly do another parity with write corrections enabled.

This should report the same number of errors as Unraid does not distinguish between one that are being corrected and those that are not.  It is only on the next check that the reported value should return to zero.

[KimoB]

Just wanted to provide an update.  I am running another parity check, and it is not detecting any errors at this point.  The speeds after 50% are also much faster than they were last time.  So I am guessing it did do a correction last time it ran, which I didn't think it did on the scheduled parity check since I have it set to NO.  (or at least I thought I did.)

[trurl]

5 minutes ago, HomeUnraidServer said:

I am guessing it did do a correction last time it ran, which I didn't think it did on the scheduled parity check since I have it set to NO.  (or at least I thought I did.)

Easy enough to check that setting.

[KimoB]

1 hour ago, trurl said:

Easy enough to check that setting.

I did, and it is set to NO, so the mystery continues

Edited January 4, 2023 by HomeUnraidServer

[KimoB]

My subsequent parity checks are coming back as clean, so I suspect i rant into the empty space parity issue.