Can Zope OFS span filesystems?
Hi All, 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). Also, can you specify a raw device (e.g. /dev/hda8 ) as the storage file (in other words, treat it as if Zope were the filesystem, instead of hosting the OFS on an underlying filesystem)? (I actually haven't figured out how to change the storage at all yet, though the ZEO documentation makes it pretty clear that it can be done). 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? For that matter, has anyone actually run Zope with an OFS that large? It's still very academic for me, though I see a possibility of things going that way, depending on how we design. So really I'm asking "Should I try to avoid huge storage in Zope?" Thanks, Terry -- ------------------------------------------------------ Terry Hancock hancock@anansispaceworks.com Anansi Spaceworks http://www.anansispaceworks.com P.O. Box 60583 Pasadena, CA 91116-6583 ------------------------------------------------------
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
participants (2)
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Dieter Maurer -
Terry Hancock