Subject: Re: partition bookkeeping
To: None <>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-kern
Date: 10/04/1999 13:20:42
>> (b) [this] limits you to a max of 63 partitions per drive.  (The
>> latter seems like infinity now, perhaps, but with drives pushing
>> 100GB, I'm not at all sure it'll stay that way.)
> I doubt we'll need more than 63 partitions, but I can be wrong.

"640K ought to be enough for anybody."

I have no immediate use for anywhere near 63 partitions.  But I already
have a real-life example of needing more than 8:

/dev/sd0a         19823     9958     8873    53%    /
/dev/sd0g         74415    51555    19139    73%    /usr
/dev/sd0d         24791    19348     4203    82%    /var
/dev/sd0e         19823     3979    14852    21%    /tmp
/dev/sd0h         49599     1402    45717     3%    /local-machine
/dev/sd0i        744271   531940   175117    75%    /locals
/dev/sd0k        205375    14873   180233     8%    /backups
/dev/sd0j        496175   370624   100742    79%    /mouse
/dev/sd0f        148847    42199    99205    30%    /anne
(plus b, swap, and c, raw, which don't appear on this list - total 11).

>>> First off, the only parttiioning scheme right now which supports
>>> recursive partitioning that I know of is mbr [...]
>> Oh.  Okay, I think we're talking about different things.
> Ahhh, true.
>> By "recursive partitioning" I mean that any partition can itself be
>> partitioned.  That's "any partition".  Not "any MBR partition".
> That is something different than I've been talking about.  But I've
> really got to ask, "Why?" :-)

Why not?

To me, both lots of partitions and recursive partitioning (my
definition) are examples of things that seem stupid but are reasonably
likely to turn out to be clever.  "UNIX doesn't prevent you from doing
stupid things because that would also prevent you from doing clever

I don't know what the "clever things" are in this case.  I'm fairly
sure someone will come up with some. :-)

> [W]hy should we permit the subpartitioning on a partition when we can
> support more partitions overall?

Working with disk images?  I'm likely to be setting up a co-loc machine
before so very long.  I'll probably set it up with a small 80M drive I
have spare.  It'd be nice to be able to create an 80M partition on one
of my big disks and do all the setup there.  Currently I'd have to do
it in a file with a vnd.

To solve the MBR problem?  I really dislike throwing in a special-case
solution to this sort of problem (allowing other partitioning schemes
within an MBR partition) when a more general solution is apparent and
not that much harder (full recursive partitions).

					der Mouse

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