[dna-issues] [JBoss JIRA] Commented: (DNA-466) JCR requires connectors to expose UUID as identifier property

[Randall Hauch (JIRA)]

    [ https://jira.jboss.org/jira/browse/DNA-466?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12475652#action_12475652 ] 

Randall Hauch commented on DNA-466:
-----------------------------------

My laptop is back to running at normal speed, and I have some new numbers.  Here they are for a depth value of 1, with the measurements including a read of each node (not just computing the path):

42 samples: min=00:00:00.000; avg=00:00:00.000,408; median=00:00:00.000,001; stddev=2609310.3454792313; max=00:00:00.017,116  -> 42
42 samples: min=00:00:00.000; avg=00:00:00.000,001; median=00:00:00.000,001; stddev=1958.7584572574413; max=00:00:00.000,013  -> 0
42 samples: min=00:00:00.000; avg=00:00:00.000,001; median=00:00:00.000,001; stddev=843.8116736509215; max=00:00:00.000,005  -> 0

Note that these are quite a bit better than the previous best (in previous comment).  Also note that when loaded, the only activity being measured is the retrieval of the path.  Here are numbers with a depth value of 2:

42 samples: min=00:00:00.000; avg=00:00:00.000,1; median=00:00:00.000,001; stddev=637613.0071907062; max=00:00:00.004,183  -> 33
42 samples: min=00:00:00.000; avg=00:00:00.000,001; median=00:00:00.000,001; stddev=1644.7539084924329; max=00:00:00.000,011  -> 0
42 samples: min=00:00:00.000; avg=00:00:00.000,001; median=00:00:00.000,001; stddev=1372.0980508784678; max=00:00:00.000,009  -> 0

And with a depth value of 6:

42 samples: min=00:00:00.000; avg=00:00:00.001,794; median=00:00:00.000,001; stddev=1.1486364528995695E7; max=00:00:00.075,343  -> 1
42 samples: min=00:00:00.000; avg=00:00:00.000,001; median=00:00:00.000,001; stddev=1958.758457257441; max=00:00:00.000,013  -> 0
42 samples: min=00:00:00.000; avg=00:00:00.000,001; median=00:00:00.000,001; stddev=2385.353075972644; max=00:00:00.000,016  -> 0

Short summary is this:  the new design was optimized to maintain a cache of the node paths, and this shows in these metrics (which are very specific to this use case). Basically, getting a path for a node is negligible.  This is very important if the JCR implementation is put over a federated connector, since the federated connector relies on the paths for many of its optimizations.

> JCR requires connectors to expose UUID as identifier property
> -------------------------------------------------------------
>
>                 Key: DNA-466
>                 URL: https://jira.jboss.org/jira/browse/DNA-466
>             Project: DNA
>          Issue Type: Bug
>          Components: JCR
>    Affects Versions: 0.5
>            Reporter: Randall Hauch
>            Assignee: Randall Hauch
>            Priority: Blocker
>             Fix For: 0.6
>
>
> The JCR implementation currently expects connectors to return a UUID as the identifier property.  This is obviously incorrect, as it goes against several of the connectors we've already implemented.  In particular, the SessionCache is expecting to find the UUID, and submits requests to the source with only the UUID (not the path).

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira