
Citus' Replication Model: Today and Tomorrow - aamederen
https://www.citusdata.com/blog/2016/12/15/citus-replication-model-today-and-tomorrow/
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elvinyung
Somewhat tangential, but I'm kind of sad that not much more was done with
pg_paxos[1].

Group Replication[2] just made it into MySQL 5.7.17 and is GA; it uses a
variant of Paxos to commit transactions. Even though most people will probably
do fine with streaming replication or semisync, it would be nice to have
support in Postgres for use cases that need an even stronger level of
consistency.

1:
[https://github.com/citusdata/pg_paxos](https://github.com/citusdata/pg_paxos)

2: [http://mysqlhighavailability.com/mysql-group-replication-
a-q...](http://mysqlhighavailability.com/mysql-group-replication-a-quick-
start-guide/)

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thepumpkin1979
What would be the advantage of Citus over AWS Aurora or AWS RDS?

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craigkerstiens
Craig from Citus here, RDS is great if you're data fits and performs well on a
single node (if your data stays under ~ 100 GB there is really no reason to
think about sharding and distributing your data). Whether you need to scale
out depends heavily on your workload, some applications are just fine to scale
storage, others need to scale memory and compute. Citus in that sense is a bit
different from RDS as well as Aurora as we extend Postgres to distribute your
data across multiple nodes. Thus, when you add a node to the cluster you get
an increase in storage, memory, and cores that are doing work for you.

~~~
CaveTech
RDS is performant well above 100 GB. Not to say citus isn't a good product,
but to imply sharing is required anywhere near the 100 GB threshold is a bit
disengenous.

Note if using aurora you also get an increase in memory and cores if using
multiple nodes...

~~~
daurnimator
I believe he was suggesting a lower bound. ==> If you're over 100GB you should
probably have a discussion around future plans and what you'll need to do to
scale to 10 times that while keeping response times etc.

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javitury
I've been interested in PG sharding for a few months. I mostly hear about this
citus extension, but what about postgres-XL? Does any one has had any
experience to compare against citus?

~~~
ddorian43
XL has too many moving parts (coordinator + data node + gtm + gtm slaves) and
no (auto) high availability

