On Sun, Mar 22, 2020 at 4:29 AM Gionatan Danti <g.danti at assyoma.it> wrote:> Il 2020-03-21 21:02 Strahil Nikolov ha scritto: > > WARNING: DO NOT DISABLE SHARDING!!! > > EVER! > > Sorry to hijack, but I am genuinely curious: why sharding should not be > disabled? What does happen if/when disabling sharding? > >When 'Sharding' is enabled, a single file gets broken into multiple files, based on offset. But when one does 'readdir()' (ie, ls), those files are hidden, and only the valid entry is shown from the Shard xlator in the graph. Now, when shard is disabled, these files are exposed directly on the mountpoint, confusing the user, and making the previously successfully written files inaccessible. Hope this helps you to understand why disabling Shard once enabled is hard! -Amar> Thanks. > > -- > Danti Gionatan > Supporto Tecnico > Assyoma S.r.l. - www.assyoma.it [1] > email: g.danti at assyoma.it - info at assyoma.it > GPG public key ID: FF5F32A8 > ________ > > > > Community Meeting Calendar: > > Schedule - > Every 2nd and 4th Tuesday at 14:30 IST / 09:00 UTC > Bridge: https://bluejeans.com/441850968 > > Gluster-users mailing list > Gluster-users at gluster.org > https://lists.gluster.org/mailman/listinfo/gluster-users >-- -- https://kadalu.io Container Storage made easy! -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.gluster.org/pipermail/gluster-users/attachments/20200322/077684ab/attachment.html>
On March 22, 2020 7:55:16 AM GMT+02:00, Amar Tumballi <amar at kadalu.io> wrote:>On Sun, Mar 22, 2020 at 4:29 AM Gionatan Danti <g.danti at assyoma.it> >wrote: > >> Il 2020-03-21 21:02 Strahil Nikolov ha scritto: >> > WARNING: DO NOT DISABLE SHARDING!!! >> > EVER! >> >> Sorry to hijack, but I am genuinely curious: why sharding should not >be >> disabled? What does happen if/when disabling sharding? >> >> >When 'Sharding' is enabled, a single file gets broken into multiple >files, >based on offset. But when one does 'readdir()' (ie, ls), those files >are >hidden, and only the valid entry is shown from the Shard xlator in the >graph. > >Now, when shard is disabled, these files are exposed directly on the >mountpoint, confusing the user, and making the previously successfully >written files inaccessible. > >Hope this helps you to understand why disabling Shard once enabled is >hard! > >-Amar > > >> Thanks. >> >> -- >> Danti Gionatan >> Supporto Tecnico >> Assyoma S.r.l. - www.assyoma.it [1] >> email: g.danti at assyoma.it - info at assyoma.it >> GPG public key ID: FF5F32A8 >> ________ >> >> >> >> Community Meeting Calendar: >> >> Schedule - >> Every 2nd and 4th Tuesday at 14:30 IST / 09:00 UTC >> Bridge: https://bluejeans.com/441850968 >> >> Gluster-users mailing list >> Gluster-users at gluster.org >> https://lists.gluster.org/mailman/listinfo/gluster-users >>Hey Amar, I was thinking if it's possible to retrieve a sharded file from the brick by concatenating the file + all shards one after another. Do you think that this is possible ? Best Regards, Strahil Nikolov
Il 2020-03-22 06:55 Amar Tumballi ha scritto:> When 'Sharding' is enabled, a single file gets broken into multiple > files, based on offset. But when one does 'readdir()' (ie, ls), those > files are hidden, and only the valid entry is shown from the Shard > xlator in the graph.Sure.> Now, when shard is disabled, these files are exposed directly on the > mountpoint, confusing the user, and making the previously successfully > written files inaccessible.Ok, I was missing this piece - that single shards become themselves visible. This will crearly wreak havoc on user application. In such cases, would re-enabling sharding fix the problem?> Hope this helps you to understand why disabling Shard once enabled is > hard!Thanks, it was very helpful. -- Danti Gionatan Supporto Tecnico Assyoma S.r.l. - www.assyoma.it [1] email: g.danti at assyoma.it - info at assyoma.it GPG public key ID: FF5F32A8