On 11/10/20 10:24 PM, Jorge Fábregas wrote:
> Hi everyone,
>
> I'm new to Linux RAID. I've searched for a clear explanation on this but
> couldn't find it.
>
> How does the "Events" counter (as shown with mdadm --examine) gets
> incremented? On what sort of events?
>
> I was initially confused about the "Events" (thinking on the different
> events as reported by mdadm --monitor) but I see this is another thing.
> I've seen explanations about it incrementing after performing writes but
> I've done some test writes and I don't see the counters changing at all
> on my RAID1 arrays. I've also seen explanations that it increments
> whenever there are changes to the superblock?
>
> Thank you.
>
The events is related with (struct mddev) mddev->events.
you can search it in kernel source code.
and the 'events' is also recorded in md metadata area, with struct:
```
struct mdp_superblock_1 {
... ...
__le64 events; /* incremented when superblock updated */
... ...
};
```
