db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Kathey Marsden (JIRA)" <j...@apache.org>
Subject [jira] Updated: (DERBY-4050) Multithreaded clob update causes growth in table that does not get reclaimed
Date Mon, 09 Feb 2009 21:13:59 GMT

     [ https://issues.apache.org/jira/browse/DERBY-4050?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Kathey Marsden updated DERBY-4050:
----------------------------------

    Attachment: derby-4050_diff2.txt

attached is an updated patch derby-4050_diff2.txt which 
- fixes formatting issues pointed out by Kristian.
- Adds recommended debug output suggested by Mike.
- Makes it easy to configure the number of threads for ClobReclamationTest.  I ran with 100
threads and saw 201 NUMALLOCATEDPAGES which is expected I think for 100 rows.  Without the
patch it grew to something so scary I aborted the test for fear of running out of space on
my laptop.  The checked in test will remain at 2 threads.
- Changes the test to set derby.debug.true to DaemonThread so we can see any interesting output
as it runs.




> Multithreaded clob update causes growth in table that does not get reclaimed
> ----------------------------------------------------------------------------
>
>                 Key: DERBY-4050
>                 URL: https://issues.apache.org/jira/browse/DERBY-4050
>             Project: Derby
>          Issue Type: Bug
>          Components: Store
>    Affects Versions: 10.2.2.0, 10.3.3.0, 10.4.2.0, 10.5.0.0
>            Reporter: Kathey Marsden
>            Assignee: Kathey Marsden
>         Attachments: ClobGrowth.java, derby-4050_diff.txt, derby-4050_diff2.txt, derby-4050_more_debug.diff,
derby.log.growth, derby.log.nogrowth, releaseNote.html
>
>
> Doing a multithreaded update of a Clob table causes table growth that does not get reclaimed
except by compressing the table.  The reproduction has a table with two threads. One  thread
 updates row 1 repeatedly with 33,000 character clob. The other thread updates row 2 with
a small clob, "hello".  The problem occurs back to 10.2 but seems much worse on trunk than
10.2.   The trunk database grew to 273MB on trunk after 10000 updates of each row. The 10.2
database grew only to 25MB.  If the update is synchronized there is no growth.
> I will attach the repro.

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


Mime
View raw message