[ 
https://issues.apache.org/jira/browse/JCR-926?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Jukka Zitting updated JCR-926:
------------------------------

    Attachment: DataStore2.patch

Attached a prototype patch that integrates the data store concept in 
Jackrabbit. The integration is very ugly at this stage and the attached code is 
definitely not meant for inclusion as-is.

For very rough performance testing I created a simple test application that 
creates a versionable folder with 100 files in it, each containing about 270kB 
of application/octet-stream data. Once populated, the entire folder was checked 
into the version store. The numbers, averaged over a couple of test runs, are: 

Current svn trunk:

    100 added files: 5625 milliseconds
    checkin everything: 11094 milliseconds

With this patch:

    100 added files: 2750 milliseconds
    checkin everything: 1906 milliseconds


> Global data store for binaries
> ------------------------------
>
>                 Key: JCR-926
>                 URL: https://issues.apache.org/jira/browse/JCR-926
>             Project: Jackrabbit
>          Issue Type: New Feature
>          Components: core
>            Reporter: Jukka Zitting
>         Attachments: DataStore.patch, DataStore2.patch
>
>
> There are three main problems with the way Jackrabbit currently handles large 
> binary values:
> 1) Persisting a large binary value blocks access to the persistence layer for 
> extended amounts of time (see JCR-314)
> 2) At least two copies of binary streams are made when saving them through 
> the JCR API: one in the transient space, and one when persisting the value
> 3) Versioining and copy operations on nodes or subtrees that contain large 
> binary values can quickly end up consuming excessive amounts of storage space.
> To solve these issues (and to get other nice benefits), I propose that we 
> implement a global "data store" concept in the repository. A data store is an 
> append-only set of binary values that uses short identifiers to identify and 
> access the stored binary values. The data store would trivially fit the 
> requirements of transient space and transaction handling due to the 
> append-only nature. An explicit mark-and-sweep garbage collection process 
> could be added to avoid concerns about storing garbage values.
> See the recent NGP value record discussion, especially [1], for more 
> background on this idea.
> [1] 
> http://mail-archives.apache.org/mod_mbox/jackrabbit-dev/200705.mbox/[EMAIL 
> PROTECTED]

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.

Reply via email to