Re: [PROPOSAL] Add SCTP network protocol to postgresql backend and frontend

On Wed, 23 Mar 2016 10:13:42 -0300
Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> wrote:

> Andreas Karlsson escribió:
> > On 03/23/2016 01:55 PM, Eduardo Morras wrote:
> > >Benefits:
> > >
> > >Dynamic multihoming, modifiable at run time, don't need aggregate
> > >links at OS level or shutdown servers/clients for a hardware or
> > >topology network change. Message oriented connection. Message
> > >reliability. Inmune to SYN floods that affect tcp.
> > >Assimetric multihoming, a client with 4 links(3x 1GbEth + wifi)
> > >can connect to a server with 1 link (10GbEth). Metadata connection
> > >messages.
> >
> > While SCTP has some nice advantages in general (I think it is a
> > pity it is not used more) I wonder how well these benefits
> > translate into the database space. Many databases are run either in
> > a controlled server environment with no direct access from the
> > Internet, or locally on the same machine as the application. In
> > those environments you generally do not have to worry about SYN
> > floods or asymmetric links.
>
> That might or might not be the most common cases, but replication
> across the ocean and similar long-range setups are a reality today
> and their use will only increase.
>
> I wonder about message ordering. Is it possible to get messages out
> of order in SCTP? Say if you have an ordered resultset stream from
> the server, it would be disastrous to get the data messages out of
> order.

Message ordering is optional, server decides if clients can use messages out of order as received or strictly in the same order as sended.

> --
> Álvaro Herrera http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

--- ---
Eduardo Morras <emorrasg(at)yahoo(dot)es>