Re: Horizontal scalability/sharding

On 2015-09-02 19:57, Josh Berkus wrote:
> On 09/01/2015 04:14 PM, Petr Jelinek wrote:
>> On 2015-09-02 00:09, Josh Berkus wrote:
>>> Not really, the mechanism is different and the behavior is different.
>>> One critical deficiency in using binary syncrep is that you can't do
>>> round-robin redundancy at all; every redundant node has to be an exact
>>> mirror of another node. In a good HA distributed system, you want
>>> multiple shards per node, and you want each shard to be replicated to a
>>> different node, so that in the event of node failure you're not dumping
>>> the full load on one other server.
>>>
>>
>> This assumes that we use binary replication, but we can reasonably use
>> logical replication which can quite easily do filtering of what's
>> replicated where.
>
> Is there a way to do logical synchronous replication? I didn't think
> there was.
>

Yes, the logical replication has similar syncrep properties as the
binary one (feedback works same way).

--
Petr Jelinek http://www.2ndQuadrant.com/
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