[ZODB-Dev] RelStorage and BLOBs

[Christian Theune]

On Tue, May 06, 2008 at 01:47:45PM -0600, Shane Hathaway wrote:
> David Durham, Jr. wrote:
>> My questions is whether or not RelStorage supports BLOBs.  My
>> situation is that I have a Plone site with user uploaded images and
>> other files, that should presumably be stored as BLOBs with
>> RelStorage.  I'm open to placing BLOBs outside of RelStorage if that's
>> reasonably accomplished.
>
> I think an NFS mount is still a better place for BLOBs than a relational  
> database.  If we put BLOBs in a relational database, we'd have to  
> carefully dance with inter-thread connections and simulated file handles  
> that may stay open for a long time.  With NFS those concerns are already  
> taken care of.
>
> The normal way to set up BLOB storage in zope.conf is to create a  
> <blobstorage> wrapper around a storage configuration.  That might just  
> work with RelStorage, but I haven't tried it yet.

At leasts its a scenario that is intended to work. I'd be happy about feedback
of people who use it.

>> The whole point of using RelStorage, for me, is reliability since I
>> can use Oracle features to improve failure scenarios.  I realize that
>> Zope sells a replication product, but I will not be able to obtain
>> funding for this.  I'm also curious if something like ZeoRAID would be
>> more appropriate for my usage scenario.
>
> Well, I think RelStorage is up to the task, though the capability has  
> not yet been proven.

I'm kind of curious what a match of RelStorage and ZEORaid may give. FWIW my
experiences with Postgresql replication aren't that good so you could still go
that route using two RelStorages with one (or more) ZEORaids in front.

Christian

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