[jira] [Comment Edited] (JCR-4007) CachingDataStore - touching every time on getRecord() was unnecessary

["Woonsan Ko (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/JCR-4007?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15440596#comment-15440596 ] 

Woonsan Ko edited comment on JCR-4007 at 8/27/16 4:00 AM:
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If I understood it correctly, JCR-3817 was originally about asynchronous touching when {{org.apache.jackrabbit.core.gc.GarbageCollector}} starts marking. When {{org.apache.jackrabbit.core.gc.GarbageCollector}} starts marking, it invokes {{DataStore.updateModifiedDateOnAccess(long)}} with current timestamp, and it resets it to 0 back after marking done.
So, a {{DataStore}} is supposed to update lastModifiedDate when reading a record *only during* the marking process of the {{GarbageCollector}}, not every time in {{getRecord()}} operation. It should not update last modified timestamp if GarbageCollector is not working.
With JCR-3817 fix, it seems to have touched records every time in {{#getRecord()}} without considering the {{minModifiedDate}} value (set by {{#updateModifiedDateOnAccess(long)}} by {{GarbageCollector}}). This was unnecessary and causing a performance degrade.
Therefore, the fix should be to invoke {{#touchInternal()}} only when {{minModifiedDate}} is greater than zero.


was (Author: woon_san):
If I understood it correctly, JCR-3817 was originally about asynchronous touching when {{org.apache.jackrabbit.core.gc.GarbageCollector}} starts marking. When {{org.apache.jackrabbit.core.gc.GarbageCollector}} starts marking, it invokes {{DataStore.updateModifiedDateOnAccess(long)}} with current timestamp, and it resets it to 0 back after marking done.
So, a {{DataStore}} is supposed to update lastModifiedTimestamp when reading a record *only during* the marking process of the {{GarbageCollector}}, not every time in {{getRecord()}} operation. It should not update last modified timestamp if GarbageCollector is not working.
With JCR-3817 fix, it seems to have touched records every time in {{#getRecord()}} without considering the {{minModifiedDate}} value (set by {{#updateModifiedDateOnAccess(long)}} by {{GarbageCollector}}. This was unnecessary and causing a performance degrade.
Therefore, the fix should be to invoke {{#touchInternal()}} only when {{minModifiedDate}} is greater than zero.

> CachingDataStore - touching every time on getRecord() was unnecessary
> ---------------------------------------------------------------------
>
>                 Key: JCR-4007
>                 URL: https://issues.apache.org/jira/browse/JCR-4007
>             Project: Jackrabbit Content Repository
>          Issue Type: Bug
>    Affects Versions: 2.13.2
>            Reporter: Woonsan Ko
>             Fix For: 2.13.3
>
>
> At the moment, {{CachingDataStore#getRecord()}} always invokes {{#touchInternal()}}, resulting in touching the file *every time* through the backend whenever reading a record. This seems to cause a performance degrade even when cached locally.
> Touching (updating the lastModifiedDate) must not be done every time. It should be done only when {{minModifiedDate}} is set to a number greater than zero by {{org.apache.jackrabbit.core.gc.GarbageCollector}} while marking.



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