[Zope] Can Zope OFS span filesystems?

Dieter Maurer dieter@handshake.de
Wed, 19 Jun 2002 20:17:06 +0200


Terry Hancock writes:
 > I've only just gotten to the point of trying to understand
 > the Zope storage systems (i.e. ZODB, ZEO, etc), and it's
 > not clear to me from what I've read online so far whether
 > its possible to have a very large OFS span across multiple
 > filesystems. I.e. can you mount sections of your Zope
 > tree on separate disks, and if so, is it transparent to
 > Zope? (With Unix/Linux FSs, you just buy more hard
 > drives if you run out of space, but AFAIK, you can't
 > actually span a file across multiple drives).
You may look at the "Mountable Storage" product.

It will not give you complete transparency, though.
But that, you don not have an Unix as well (e.g. not hard
links, no "rename").

 > Also, can you specify a raw device (e.g. /dev/hda8 )
 > as the storage file
I would be surprised if that would be supported.

 > ...
 > I've seen solutions which try to avoid having massive
 > content like this inside of Zope.  Are they really
 > necessary? Or could you basically use Zope as the 
 > filesystem?  Any pros or cons I ought to know about?
If I have millions of objects, I do not put them into the
ZODB but in an external database. There, search support is better and
there are optimizations for large amounts of regular data.

If I have lots of blob like objects, I put then into the filesystem.
This is far better for backup than putting them into the ZODB (which
is a single large file, difficult to backup incrementally) and
far better for speed than putting then into a database.



Dieter