From mboxrd@z Thu Jan 1 00:00:00 1970 References: <1438f48b-0a6d-4fb7-92dc-3688251e0a00@assyoma.it> <2f9c4346d4e9646ca058efdf535d435e@xenhideout.nl> <5df13342-8c31-4a0b-785e-1d12f0d2d9e8@redhat.com> <6dd12ab9-0390-5c07-f4b7-de0d8fbbeacf@redhat.com> <3831e817d7d788e93a69f20e5dda1159@xenhideout.nl> <0ab1c4e1-b15e-b22e-9455-5569eeaa0563@redhat.com> <51faeb921acf634609b61bff5fd269d4@xenhideout.nl> <4b4d56ef-3127-212b-0e68-00b595faa241@redhat.com> <6dd3a268-8a86-31dd-7a0b-dd08fdefdd55@redhat.com> <9142007eeb745a0f4774710b7c007375@assyoma.it> <0a322a6f355a0744427f2a7a45162c81@assyoma.it> <1be887bb-d86f-5896-1c19-844864c41ba2@redhat.com> From: Zdenek Kabelac Message-ID: Date: Thu, 1 Mar 2018 17:00:17 +0100 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Content-Transfer-Encoding: quoted-printable Subject: Re: [linux-lvm] Snapshot behavior on classic LVM vs ThinLVM Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="iso-8859-1"; format="flowed" To: linux-lvm@redhat.com, Gionatan Danti Dne 1.3.2018 v 13:48 Gionatan Danti napsal(a): >=20 > On 01/03/2018 12:23, Zdenek Kabelac wrote: >> In general - for extX=EF=BF=BD it's remount read-only upon error - which= works for=20 >> journaled metadata - if you want same protection for 'data' you need to = >> switch to rather expensive data journaling mode. >> >> For XFS there is now similar logic where write error on journal stops=20 >> filesystem usage - look far some older message (even here in this list) = it's=20 >> been mentioned already few times I guess... >=20 There is quite 'detailed' config for XFS - just not all settings are probably tuned in the best way for provisioning. See: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/ht= ml/storage_administration_guide/xfs-error-behavior >=20 >> Unfreezed filesystem is simply not usable... >=20 > I was speaking about unfreezed thin metadata snapshot - ie:=20 > reserve_metadata_snap *without* a corresponding release_metadata_snap. Wi= ll=20 > that cause problems? >=20 metadata snapshot 'just consumes' thin-pool metadata space, at any time there can be only 1 snapshot - so before next usage you have to drop the existing one. So IMHO it should have no other effects unless you hit some bugs... > I think VDO is a fruit of Permabit acquisition, right? As it implements i= t's=20 > own thin provisioning, will thinlvm migrate to VDO or it will continue to= use=20 > the current dmtarget? thin-pool target is having different goals then VDO so both targets will likely live together. Possibly thin-pool might be tested for using VDO data volume if it makes an= y=20 sense... Regards Zdenek