> ??? Mhm, there seems to be a big misunderstanding.
> If you just specify ONE devspace with 100 000 pages, i.e.
> tell the kernel DEVSPACE_NAME and DEVSPACE_SIZE,
> then your database has not more than 100 000 pages, no matter
> how many devspaces you COULD have specified. This
> maximum number is given by MAXDEVSPACES.

Right, I understand that. The default for MAXDATAPAGES seems to be over a
million though. So I would be limited to 10 devspaces. I put it at 100
because I'm lazy.

> But the kernel is not able, not allowed (how should it do it?)
> to say, 'ok, those pages whose number (100 000) I know and
> of which I know the name of the devspace are full, lets create
> a new file or raw device somewhere on the users disks, name it
> somehow, specify a size I, the kernel, would like and fill it.'

Ah, that is too bad. It would be nice because (say) I start with a database
that is 25MB but grows to 2GB, but I have 50 GB of space? I should be able
to say: divide yourself into chunks of 650MB (convenient size for burning
CDs, or whatever) and extend yourself out as long as you don't top 50GB! :)

> is full, the USER/ADMINISTRATOR of the database has to decide, where
> and how much additional disk-space the database may use.

I agree, but I should be able to specify something like the above:

division size is (X) MB. total possible size is (X) MB. it should be that
simple. I don't care about "data pages" that's a meaningless number to me. I
need to know how this relates to the filesystem, and the above makes good
sense. It is extremely minor, but still an important point.

> Each table/index/meta-data of the database is allowed to be stored
> at ANY devspace used for this database. It is spread over all devspaces

I do understand that. I would be horrified if that was not the case :)

> available. Therefore it does not matter if you have 50 devspaces
> each with 100 000 pages or one huge devspace if you want to store a table
> which will need much more than those 100 000 pages available on ONE small
> devspace.

Which is precisely why I think devspaces need only be defined in "chunk
size" and "maximum size of all chunks" because the user doesn't actually
care about anything else: the numbers are arbitrary so don't scare people
with the thought that they might _not_ be arbitrary and somehow affect the
performance of the database. I don't need to know that much.

> Things are a little bit different to Oracle.

In general, I think you have done a much better job than oracle, especially
with the tools. Most things are clear and simple, which is what I like. In
this case, though, I think Oracle handles storage definition in a more
sensible way.

minor point :)

-alex


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