Pool not detected

[mrnickgbk]

Hello,

Using ./thin_shrink.py -L 460G -t data-volume-group/data-thin-pool

I get this error:

Warning: No tpool device found, perhaps pool has no thins?

But these are the correct vg and pool name:

From running lvs
LV VG Attr LSize Pool Origin Data% Meta%
data-thin-pool data-volume-group twi-aotz-- 465.67g

Could it be the dashes causing an issue with the name? dmstatus reports the name with --

[nkshirsagar]

Are there any thin logical volumes created in the pool ? And this tool is not yet integrated into lvm2 so the freed up space will not be released back to the volume group today. Secondly, if there are snapshots in the thin pool, it's buggy. So be aware this is wip BUT I appreciate that you're testing it out ..

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On Tue, 2 Feb, 2021, 10:12 pm mrnickgbk, ***@***.***> wrote: Hello, Using ./thin_shrink.py -L 460G -t data-volume-group/data-thin-pool I get this error: Warning: No tpool device found, perhaps pool has no thins? But these are the correct vg and pool name: From running lvs LV VG Attr LSize Pool Origin Data% Meta% data-thin-pool data-volume-group twi-aotz-- 465.67g Could it be the dashes causing an issue with the name? dmstatus reports the name with -- — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#1>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ADNFUF7XSYJ3E5G3ACJIXBDS5ATOVANCNFSM4W7AO65A> .

[mrnickgbk]

Appreciate the quick reply.

There are thin lv's yes

I'm using RHEL7 (LVM2). So you say the free'd up space will not be released? I was looking to reclaim some extents to increase metadata partition. Is that nor possible with this tool then?

And yes there are snapshots.

Thanks!

[nkshirsagar]

No, this tool will be rewritten in rust and then integrated with lvm2 so that the tdata reduction is then possible (this tool does not resize tdata today gracefully.. it can do it with a forced vgcfgrestore with a changed mapping in the vg metadata. But for the released space to be given back to the volume group needs integration in lvm2. It's planned for a future release. I'm not sure though why it's not working on your setup if it has thin logical volumes. I'll debug it later if you send me lvs -a and a console output..

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On Wed, 3 Feb, 2021, 1:38 am mrnickgbk, ***@***.***> wrote: Appreciate the quick reply. There are thin lv's yes I'm using RHEL7 (LVM2). So you say the free'd up space will not be released? I was looking to reclaim some extents to increase metadata partition. Is that nor possible with this tool then? And yes there are snapshots. Thanks! — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#1 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ADNFUF74LQ5VOTV2I522ATLS5BLR7ANCNFSM4W7AO65A> .

[mrnickgbk]

Thanks for the info .

Ah so it would not help me anyhow, as I need to reclaim extents. I'd be interested in the vgconfigrestore option if that was available / documented - this is a production system and your tool is pretty much my last resort before having to blow away the lvm config and data :(

I'll happily send you the lvs output but I'd prefer not to post it here for all to see. Is there an email I can contact you on?

[nkshirsagar]

[email protected] And yes we can discuss further over email and I can put you in touch with the upstream maintainer who's working on the rust verson and you could get more information about the eventual release upstream with lvm integration (tdata reduction and vg space reclaim). This tool currently does metadata changes and data copying to make the pool shrinkable. The rest is just a demo to show the reduced size currently with a forced vgcfgrestore, not meant to be the final approach for the space to be seen in the vg. lvreduce will do the lvm2 and dm side changes for proper space reclaim to the volume group. This is all wip.

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On Wed, 3 Feb, 2021, 2:05 am mrnickgbk, ***@***.***> wrote: Thanks for the info . Ah so it would not help me anyhow, as I need to reclaim extents. I'll happily send you the output but I'd prefer not to post it here for all to see. Is there an email I can contact you on? — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#1 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ADNFUF5S6Z3QFSLA7DQ27BLS5BOXXANCNFSM4W7AO65A> .