Re: zerofree btrfs support?

Hey. On Wed, 2018-03-14 at 20:38 +0100, David Sterba wrote: > I have a prototype code for that and after the years, seeing the > request > again, I'm not against adding it as long as it's not advertised as a > security feature. I'd expect that anyone in the security area should know that

Re: zerofree btrfs support?

On Sat, Mar 10, 2018 at 03:55:25AM +0100, Christoph Anton Mitterer wrote: > Hi. > > Just wondered... was it ever planned (or is there some equivalent) to > get support for btrfs in zerofree? The zerofree was requested, eg. here https://bugzilla.kernel.org/show_bug.cgi?id=69121 and there was a

Re: zerofree btrfs support?

On Sat, 2018-03-10 at 23:31 +0500, Roman Mamedov wrote: > QCOW2 would add a second layer of COW > on top of > Btrfs, which sounds like a nightmare. I've just seen there is even a nocow option "specifically" for btrfs... it seems however that it doesn't disable the CoW of qcow, but rather that of

Re: zerofree btrfs support?

On Sat, 10 Mar 2018 16:50:22 +0100 Adam Borowski wrote: > Since we're on a btrfs mailing list, if you use qemu, you really want > sparse format:raw instead of qcow2 or preallocated raw. This also works > great with TRIM. Agreed, that's why I use RAW. QCOW2 would add a

Re: zerofree btrfs support?

On Sat, 2018-03-10 at 16:50 +0100, Adam Borowski wrote: > Since we're on a btrfs mailing list Well... my original question was whether someone could make zerofree support for btrfs (which I think would be best if someone who knows how btrfs really works)... thus I directed the question to this

Re: zerofree btrfs support?

On Sat, 2018-03-10 at 19:37 +0500, Roman Mamedov wrote: > Note you can use it on HDDs too, even without QEMU and the like: via > using LVM > "thin" volumes. I use that on a number of machines, the benefit is > that since > TRIMed areas are "stored nowhere", those partitions allow for > incredibly

Re: zerofree btrfs support?

On Sat, Mar 10, 2018 at 07:37:22PM +0500, Roman Mamedov wrote: > Note you can use it on HDDs too, even without QEMU and the like: via using LVM > "thin" volumes. I use that on a number of machines, the benefit is that since > TRIMed areas are "stored nowhere", those partitions allow for incredibly

Re: zerofree btrfs support?

On Sat, 10 Mar 2018 15:19:05 +0100 Christoph Anton Mitterer wrote: > TRIM/discard... not sure how far this is really a solution. It is the solution in a great many of usage scenarios, don't know enough about your particular one, though. Note you can use it on HDDs too,

Re: zerofree btrfs support?

On Sat, 2018-03-10 at 09:16 +0100, Adam Borowski wrote: > Do you want zerofree for thin storage optimization, or for security? I don't think one can really use it for security (neither on SSD or HDD). On both, zeroed blocks may still be readable by forensic measures. So optimisation, i.e. digging

Re: zerofree btrfs support?

On Sat, Mar 10, 2018 at 03:55:25AM +0100, Christoph Anton Mitterer wrote: > Just wondered... was it ever planned (or is there some equivalent) to > get support for btrfs in zerofree? Do you want zerofree for thin storage optimization, or for security? For the former, you can use fstrim; this is