That doesn't solve the same problem. Dedicating a remote server for the
system tables still means that all the master to system tables mutations
and reads are done over rpc. That still means that the most important
operations are competing for rpc queue time.

On Fri, Nov 18, 2016 at 11:37 AM, Francis Liu <tof...@ymail.com.invalid>
wrote:

> Just some extra bits of information:
>
> Another way to isolate user regions from meta is you can create a
> regionserver group (HBASE-6721) dedicated to the system tables. This is
> what we do at Y!. If the load on meta gets too high (and it does), we split
> meta so the load gets spread across more regionservers (HBASE-11165) this
> way availability for any client is not affected. Tho agreeing with Stack
> that something is really broken if high priority rpcs cannot get through to
> meta.
> Does single writer to meta refer to the zkless assignment feature? If
> isn't that feature has been available since 0.98.6 (meta _not_ on master)?
> and we've been running with it on all our clusters for quite sometime now
> (with some enhancements ie split meta etc).
> Cheers,Francis
>
>     On Wednesday, November 16, 2016 10:47 PM, Stack <st...@duboce.net>
> wrote:
>
>
>  On Wed, Nov 16, 2016 at 10:44 PM, Stack <st...@duboce.net> wrote:
>
> > On Wed, Nov 16, 2016 at 10:57 AM, Gary Helmling <ghelml...@gmail.com>
> > wrote:
> >
> >>
> >> Do you folks run the meta-carrying-master form G?
> >
> > Pardon me. I missed a paragraph. I see you folks do deploy this form.
> St.Ack
>
>
>
>
>
> > St.Ack
> >
> >
> >
> >
> >
> >>
> >>
> >> > > >
> >> > > Is this just because meta had a dedicated server?
> >> > >
> >> > >
> >> > I'm sure that having dedicated resources for meta helps.  But I don't
> >> think
> >> > that's sufficient.  The key is that master writes to meta are local,
> and
> >> do
> >> > not have to contend with the user requests to meta.
> >> >
> >> > It seems premature to be discussing dropping a working implementation
> >> which
> >> > eliminates painful parts of distributed consensus, until we have a
> >> complete
> >> > working alternative to evaluate.  Until then, why are we looking at
> >> > features that are in use and work well?
> >> >
> >> >
> >> >
> >> How to move forward here? The Pv2 master is almost done. An ITBLL
> bakeoff
> >> of new Pv2 based assign vs a Master that exclusively hosts hbase:meta?
> >>
> >>
> >> I think that's a necessary test for proving out the new AM
> implementation.
> >> But remember that we are comparing a feature which is actively
> supporting
> >> production workloads with a line of active development.  I think there
> >> should also be additional testing around situations of high meta load
> and
> >> end-to-end assignment latency.
> >>
> >
> >
>
>
>
>

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