Re: Changeset Extraction v7.6.1

On 5/31/14, 9:11 AM, Andres Freund wrote:
> On 2014-02-21 15:14:15 -0600, Jim Nasby wrote:
>> On 2/17/14, 7:31 PM, Robert Haas wrote:
>>> But do you really want to keep that snapshot around long enough to
>>> copy the entire database?  I bet you don't: if the database is big,
>>> holding back xmin for long enough to copy the whole thing isn't likely
>>> to be fun.
>>
>> I can confirm that this would be epic fail, at least for londiste. It takes about 3 weeks for a new copy of a ~2TB
database.There's no way that'd work with one snapshot. (Granted, copy performance in londiste is rather lackluster, but
still...)
>
> I'd marked this email as todo:
> If you have such a huge database you can, with logical decoding at
> least, use a basebackup using pg_basebackup or pg_start/stop_backup()
> and roll forwards from that... That'll hopefull make such huge copies
> much faster.

Just keep in mind that one of the use cases for logical replication is upgrades.
-- 
Jim C. Nasby, Data Architect                       jim@nasby.net
512.569.9461 (cell)                         http://jim.nasby.net