repository wide namespace indexes

[Tobias Bocanegra <to...@day.com>]

hi,
in JCR-669 we introduced a global namespace index. it is used by some
persistence managers in order to keep the serialization of names small
(fewer bytes).

unfortunately causes the workspace data not to be isolated anymore.
this can be a problem when a workspace needs to be migrated to another
repository with other namespace indexes. so an easy migration is not
possible unless you export/import the entire workspace using system
view (which is almost impossible for huge workspaces).

a similar potential problem is caused by the data store, since all
workspaces share the same.
so when migrating a workspace, you would need to transfer all
respective records in the data store to the target repository.

where as the data store problem can be solved by copying the
respective items, the namespace indexes are a bigger problem, since
the serialized items need to be adjusted.

suggest to alter the bundle pm to use the already existing 'name
index' for the namespaces as well.
see https://issues.apache.org/jira/browse/JCR-1517 for a suggested patch.

--
regards, toby

Re: repository wide namespace indexes

[Jukka Zitting <ju...@gmail.com>]

Hi,

On Mon, Apr 14, 2008 at 9:02 AM, Tobias Bocanegra
<to...@day.com> wrote:
>  >  * It would be nice to document the evolution of the bundle
>  >  serialization format somewhere on the wiki or the web site.
>  i will place it into the javadoc of the BundleBinding, for now.

Good, thanks!

BR,

Jukka Zitting

Re: repository wide namespace indexes

[Tobias Bocanegra <to...@day.com>]

>  On Mon, Apr 14, 2008 at 8:32 AM, Tobias Bocanegra
>  <to...@day.com> wrote:
>  >  suggest to alter the bundle pm to use the already existing 'name
>  >  index' for the namespaces as well.
>  >  see https://issues.apache.org/jira/browse/JCR-1517 for a suggested patch.
>
>
> +1 Looks OK, comments:
>
>  * It would be nice to document the evolution of the bundle
>  serialization format somewhere on the wiki or the web site.
i will place it into the javadoc of the BundleBinding, for now.

>  * How about indexing namespace:name combinations? The indexed set is
>  probably not much larger than that of local names, and indexing the
>  combinations would drop the serialization cost (both time and space)
>  of names.
that's a good idea. i'll have a look at it.

--
toby

Re: repository wide namespace indexes

[Jukka Zitting <ju...@gmail.com>]

Hi,

On Mon, Apr 14, 2008 at 8:32 AM, Tobias Bocanegra
<to...@day.com> wrote:
>  suggest to alter the bundle pm to use the already existing 'name
>  index' for the namespaces as well.
>  see https://issues.apache.org/jira/browse/JCR-1517 for a suggested patch.

+1 Looks OK, comments:

* It would be nice to document the evolution of the bundle
serialization format somewhere on the wiki or the web site.

* How about indexing namespace:name combinations? The indexed set is
probably not much larger than that of local names, and indexing the
combinations would drop the serialization cost (both time and space)
of names.

BR,

Jukka Zitting