Re: [Tarantool-patches] [PATCH] vinyl: unthrottle scheduler on checkpoint

[Konstantin Osipov <kostja.osipov@gmail.com>]

* Nikita Pettik <korablev@tarantool.org> [20/04/27 18:40]:
> > > > > Checkpoint daemon uses directly box.snapshot(), so now we can't tell
> > > > > whether checkpoint is launched manually or automatically. To differ
> > > > > these scenarious we can make checkpoint daemon call sort of
> > > > > box.__scheduled_snapshot() (which won't be part of public API ofc).
> > > > > Then we will be able to pass boolean parameter to begin_checkpoint()
> > > > > indicating manual/auto mode. Or simply close issue as wont fix :)
> > > > 
> > > > Uhm, no, checkpoint daemon uses gc_do_checkpoint() and it doesn't
> > > > use box.snapshot().
> > > 
> > > Seems we are looking at different branches: 1.10 still uses checkpoint
> > > daemon written in Lua. If this patch should be pushed to master branch
> > > only, then I guess it would be easy to patch engine_begin_checkpoint()
> > > and make it accept argument responsible for checkpoint mode (scheduled
> > > or manual).
> > 
> > Why do you need to fix 1.10?
> 
> For instance, it would make test backporting process easier.
> Otherwise we will get different behaviours while using
> ERRINJ_VY_SCHED_TIMEOUT error injection.

Well, I guess then 1.10 will require a separate fix. 

I don't see why you even consider a possibility of unthrottling
the scheduling in all cases in 1.10. It's a stable/lts release,
and what you're trying to do is not any customer's problem, you
simply shouldn't risk breaking ppl for no good reason.


-- 
Konstantin Osipov, Moscow, Russia
https://scylladb.com