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Subject: Re: [RFC] dm-bow working prototype
To:     Paul Lawrence <paullawrence@google.com>
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From:   Wols Lists <antlists@youngman.org.uk>
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Date:   Thu, 25 Oct 2018 22:15:39 +0100
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On 25/10/18 19:13, Paul Lawrence wrote:
>> I have some questions about dm-bow:
>> – How file system agnostic this feature is planned to be? While it is
>> designed with ext4 in mind, is it going to work when used over other
>> file systems, like FAT or BTRFS for example?

> So long as the file system supports fstrim, it should work. If the file
> system creates a lot of churn say by running garbage collection, I'd not
> recommend it. And I really don't see the use case if the file system has
> any sort of snapshot capability - that will always be a superior
> solution to a block level one IMO.

Sorry for being dense, but why is this posted to linux-raid, then? Raid
does not support fstrim, and is filesystem-agnostic.

I can imagine people here being interested, but it feels to me as though
your functionality is completely orthogonal to raid. Sorry.

Cheers,
Wol