Re: finding changed blocks using WAL scanning - Mailing list pgsql-hackers

On Sat, Apr 20, 2019 at 12:21:36AM -0400, Robert Haas wrote:
> As to that, what I'm proposing here is no different than what we are
> already doing with physical and logical replication, except that it's
> probably a bit cheaper.  Physical replication reads all the WAL and
> sends it all out over the network.  Logical replication reads all the
> WAL, does a bunch of computation, and then sends the results, possibly
> filtered, out over the network.  This would read the WAL and then
> write a relatively small file to your local disk.
> 
> I think the impact will be about the same as having one additional
> standby, give or take.

Good point.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

+ As you are, so once was I.  As I am, so you will be. +
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