Re: Hadoop backend?

On Mon, Feb 23, 2009 at 9:08 AM, Paul Sheer <paulsheer(at)gmail(dot)com> wrote:
>> It would only be possible to have the actual PostgreSQL backends
>> running on a single node anyway, because they use shared memory to
>
> This is not problem: Performance is a secondary consideration (at least
> as far as the problem I was referring to).
>
> The primary usefulness is to have the data be a logical entity rather
> than a physical entity so that one can maintain physical machines
> without having to worry to much about where-is-the-data.
>
> At the moment, most databases suffer from the problem of occasionally
> having to move the data from one place to another. This is a major
> nightmare that happens once every few years for most DBAs.
> It happens because a system needs a soft/hard upgrade, or a disk
> enlarged, or because a piece of hardware fails.
>
> I have also found it's no use having RAID or ZFS. Each of these ties
> the data to an OS installation. If the OS needs to be reinstalled, all
> the data has to be manually moved in a way that is, well... dangerous.
>
> If there is only one machine running postgres that is fine too: I can have
> a second identical machine on standby in case of a hardware failure.
> That means a short amount of downtime - most people can live
> with that.

I think the performance aspect of things has to be considered. If the
system introduces too much overhead it won't be useful in practice.
But apart from that I agree with all of this.

> I read somewhere that replication was one of the goals of postgres's
> coming development efforts. Personally I think hadoop might be
> a better solution - *shrug*.
>
> Thoughts/comments ??

I think the two are solving different problems.

...Robert