ZFS secondarycache on SSD problem on r255173

[Steven Hartland]

Thats correct the new code knows the what the ashift of the underlying disk should
be so if it detects a vdev with a lower ashift you get this warning.

I suspect the issue is that cache devices don't have an ashift, so when the check
is done it gets a default value and hence the warning.

I'd have to did some more to see how ashift in cache devices is or isn't implemented.

    Regards
    Steve

----- Original Message ----- 
From: "Dmitriy Makarov" <supportme at ukr.net>
To: "Steven Hartland" <killing at multiplay.co.uk>
Cc: "Borja Marcos" <borjam at sarenet.es>; <freebsd-current at freebsd.org>; "Justin T. Gibbs" <gibbs at freebsd.org>
Sent: Monday, September 16, 2013 1:29 PM
Subject: Re[3]: ZFS secondarycache on SSD problem on r255173


> And have to say that ashift of a main pool doesn't matter.
> I've tried to create pool with ashift 9 (default value) and with ashift 12 with creating gnops over gpart devices, export pool, 
> destroy gnops, import pool. There is the same problem with cache device.
>
> There is no problem with ZIL devices, they reports ashift: 12
>
> children[1]:
> type: 'disk'
> id: 1
> guid: 6986664094649753344
> path: '/dev/gpt/zil1'
> phys_path: '/dev/gpt/zil1'
> whole_disk: 1
> metaslab_array: 67
> metaslab_shift: 25
> ashift: 12
> asize: 4290248704
> is_log: 1
> create_txg: 22517
>
> Problem with cache devices only, but in zdb output tere is nothing at all about them.
>
> --- Исходное сообщение --- 
> От кого: "Steven Hartland" < killing at multiplay.co.uk >
> Дата: 16 сентября 2013, 14:18:31
>
> Cant say I've ever had a issue with gnop, but I haven't used it for
> some time.
>
> I did have a quick look over the weekend at your issue and it looks
> to me like warning for the cache is a false positive, as the vdev
> for cache doesn't report an ashift in zdb so could well be falling
> back to a default value.
>
> I couldn't reproduce the issue for log here, it just seems to work
> for me, can you confirm what ashift is reported for your devices
> using: zdb <pool>
>
>    Regards
>    Steve
> ----- Original Message ----- 
> From: "Borja Marcos" <
>
> --- 
> Дмитрий Макаров
>
>
> --- 
> Дмитрий Макаров
> 


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