[jira] [Commented] (OAK-727) Use snapshot of namespaces in SessionImpl

["Jukka Zitting (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/OAK-727?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13888317#comment-13888317 ] 

Jukka Zitting commented on OAK-727:
-----------------------------------

Note that based on the work in OAK-924 the namespace snapshots are no longer needed for performance, so I dropped them along other changes in revision 1563143. That revision notably boosted XML import performance (with Jackrabbit results included for scale):

{noformat}
# XmlImportTest      C     min     10%     50%     90%     max       N
Jackrabbit           1    7549    7549    8186    9158    9158       4
Oak-Tar (before)     1    6435    6435    6580    6720    6720       9
Oak-Tar (after)      1    5381    5383    5479    5722    5737      10
{noformat}

> Use snapshot of namespaces in SessionImpl
> -----------------------------------------
>
>                 Key: OAK-727
>                 URL: https://issues.apache.org/jira/browse/OAK-727
>             Project: Jackrabbit Oak
>          Issue Type: Improvement
>          Components: jcr
>    Affects Versions: 0.6
>            Reporter: Marcel Reutegger
>            Priority: Minor
>             Fix For: 0.7
>
>         Attachments: OAK-727.patch, OAK-727.patch
>
>
> Importing content with the Oak XML ImportHandler makes quite heavy use of namespaces and results in frequent calls to Namespaces.getNamespaceMap(). Most of the time the complete namespace map is not actually needed and only a single mapping is requested. This adds quite some overhead, which we can easily avoid. The JCR specification says (3.5.1):
> bq. The local namespace mapping of a session is determined by the initial set of mappings copied from the namespace registry and any session-local changes made to that set.
> Right now we don't have this initial set, but always ask the namespace registry.
> I suggest we copy the mappings on first usage and work with this copy.



--
This message was sent by Atlassian JIRA
(v6.1.5#6160)