Identical disks - some slower then others (badblocks)

[Rand__]

I am running badblocks on a set of disks that showed some sata errors (cable induced I assume).

I see that one disk is running slower then the others ... I saw the same behavior with two (out of 4) on another run before this - but before that I've not run it, so I am not sure whether that's normal or not?
Why would that happen?
All 4 disks are the same model and are attached to the same HBA. On the previous run it where disk 2/3 of 4, so its not always the last one.



Is that only me or is that normal / expected ?

 

[Blinky 42]

If it is a cable error then the link could have failed back down to a slower speed.
Check your dmesg output and see if there is any mention of it there, or the utility for your HBA to see the link speed.
I would also run smartctl on the drives and see if the slow one has a lot of reallocated sectors that would cause the head to need to seek all over for sequential LBA's and slow things down.

I have also had a few drives over the years that even with different cables or controllers tend to link up at a slower speed for some reason, some odd failure mode of the controller was my guess and I wouldn't trust them and RMA'd or tossed 'em.

 

[Rand__]

I moved the disks to another box to ensure its not the cables. But will check the specific drive. Thanks