[CentOS] block level changes at the file system level?

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On 07/03/2014 12:19 PM, John R Pierce wrote:
> you do realize, adding/removing or even changing the length of a single
> line in a block of that pg_dump file will change every block after it as
> the data will be offset ?

Yes. And I guess this is probably where the conversation should end. I'm 
used to the capabilities of Mercurial DVCS as well as ZFS snapshots, and 
was thinking/hoping that this type of capability might exist in a file 
system. Perhaps it just doesn't belong there.

On 07/03/2014 12:23 PM, Les Mikesell wrote:
> But, since this is about postgresql, the right way is probably just to
> set up replication and let it send the changes itself instead of doing
> frequent dumps.

Whatever we do, we need the ability to create a point-in-time history. 
We commonly use our archival dumps for audit, testing, and debugging 
purposes. I don't think PG + WAL provides this type of capability. So at 
the moment we're down to:

A) run PG on a ZFS partition and snapshot ZFS.
B) Keep making dumps (as now) and use lots of disk space.
C) Cook something new and magical using diff, rdiff-backup, or related 
tools.

-Ben