[Pulp-dev] Transition from Mongo to Postgre

[Michael Hrivnak]

We have a thread here about a lot of the 3.0 stack choices, although it
seems to skip past the assumption that we're moving to postgres:

https://www.redhat.com/archives/pulp-list/2016-May/msg00042.html

I can't quickly find another summary of why, so I'll describe the
highlights here:

- Pulp has highly relational data. The core use case is managing the
relationships between content and repositories. Using a relational DB makes
that a lot easier.
- A schemaless DB makes it easy to do writes, but you have to be very
careful when doing reads that the your software is prepared for whatever
data structure comes out. If you want to enforce a schema, it has to be
done in software. It's doable, but requires great care.
- Transactions!
- The HA story with mongodb is more complex than most people realize
(certainly more complex than we expected). To get real HA with data safety,
you have to do a lot of the work in your own software.

MongoDB is great at what it does and a good fit for some use cases, but we
learned that it's not the best fit for Pulp.

Michael

On Tue, Sep 13, 2016 at 3:21 AM, Filip Nguyen <fnguyen at redhat.com> wrote:

> I heard that Pulp is switching from Mongo to Postgre. Just out of
> curiosity, I would like to learn more about the reasons why you decided to
> go this direction. Is there any document/email thread about it?
>
> _______________________________________________
> Pulp-dev mailing list
> Pulp-dev at redhat.com
> https://www.redhat.com/mailman/listinfo/pulp-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/pulp-dev/attachments/20160913/0cba6ff2/attachment.htm>