[tarantool-patches] [PATCH v2 0/5] Strong sequentially LSN in journal
Vladimir Davydov
vdavydov.dev at gmail.com
Mon Jan 28 14:15:08 MSK 2019
On Tue, Jan 22, 2019 at 01:31:08PM +0300, Georgy Kirichenko wrote:
> The patchset eliminates LSN gaps from journal what is needed for
> synchronous replication to enforce data stream consistency.
Could you give an example how LSN gaps can break synchronous
replication?
> Replicaset vclock is promoted only after write, replication row applying
> is allowed only if previous row was processed. All conflicting rows to
> skip are replacing with NOPs to fill gaps. After all vclock following
> protected with assert to ensure that this is strict one step increase.
It looks very much like
https://github.com/tarantool/tarantool/issues/2283
which was done by Serge P. a while back:
https://www.freelists.org/post/tarantool-patches/PATCH-replication-do-not-skip-masters-rows-in-case-of-an-error
Shouldn't we rather apply his patch? Or there's some crucial difference?
>
> Needed for: #980
>
> Changes in v2:
> - Rebased against latest 2.1
> - Fix handling rows which were returned back
>
> Issue: https://github.com/tarantool/tarantool/issues/980
> Branch:https://github.com/tarantool/tarantool/tree/g.kirichenko/gh-980-disable-lsn-gaps
>
> Georgy Kirichenko (5):
> Do not promote wal vclock for failed writes
> Update replicaset vclock from wal
> Enforce applier out of order protection
> Emit NOP if an applier skips row
> Disallow lsn gaps while vclock following
More information about the Tarantool-patches
mailing list