jackrabbit-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Marcel Reutegger <marcel.reuteg...@gmx.net>
Subject Re: [jira] Commented: (JCR-169) Make Jackrabbit clusterable
Date Fri, 01 Sep 2006 08:43:31 GMT
Ian Boston wrote:
> So, if you have 50x200MB of Lucene index... for example.... and wanted 
> that to be accessible in a cluster environment, would Jackrabbit be a 
> good place to put those segments ?

just to clarify, would this lucene index be 'application data', which 
is stored like regular content through the JCR api? Or do you mean the 
jackrabbit internal lucene segments?

> The big killer for Lucene is the ability to seek efficiently on the 
> central blob (I think), but presumably by choosing the right Binary 
> storage strategy that comes partially for free ?

Jackrabbit always copies a binary to a temp file or into memory when 
the property value is accessed. That is, the seek would always be 
local. But as I already mentioned in another thread, JCR does not 
support random access on binary properties. A binary property returns 
a plain InputStream.

> If this is the case, I could replace my, slightly odd, segment 
> distribution mechanism with Jackrabbit.

yes, you certainly get a couple of goodies you otherwise don't have. 
e.g. observation on the index files ;)

> Last question,
> Is JCR-169 being actively worked on ?

It doesn't have a high priority, but we are working on it on a 
conceptual level. discussions during coffee breaks, etc. Basically how 
the problems stated in JCR-169 can be solved and what needs to be 
changed in the core to implement the feature blocks in a clustered 

> Is there an area where another pair of hands would help... I would like 
> to be able to deploy Jackrabbit in a cluster.

One major area is how changes from one cluster node are distributed to 
other cluster nodes. Giota implemented something like a prototype, but 
I'm not sure what the current state is. See also this discussion: 

Or any other area mentioned in JCR-169, you can simply pick one ;)


View raw message