[tarantool-patches] Re: [PATCH v2 7/7] relay: join new replicas off read view

[Konstantin Osipov]

* Vladimir Davydov <vdavydov.dev at gmail.com> [19/08/19 19:57]:
> Historically, we join a new replica off the last checkpoint. As a
> result, we must always keep the last memtx snapshot and all vinyl data
> files corresponding to it. Actually, there's no need to use the last
> checkpoint for joining a replica. Instead we can use the current read
> view as both memtx and vinyl support it. This should speed up the
> process of joining a new replica, because we don't need to replay all
> xlogs written after the last checkpoint, only those that are accumulated
> while we are relaying the current read view. This should also allow us
> to avoid creating a snapshot file on bootstrap, because the only reason
> why we need it is allowing joining replicas. Besides, this is a step
> towards decoupling the vinyl metadata log from checkpointing in
> particular and from xlogs in general.
> 

How does this work given relay_* functions are running in a relay thread? 


-- 
Konstantin Osipov, Moscow, Russia