Table Lock happens for spring batch chunk item reader and writer

问题

I am working with the spring batch data loader . I have 15000 files and processing only one file using multiresource partitioner.It seems that the table lock happens when trying to insert data in to the table.There is no parallel step defined here. it is very slow for file processing. Following is the code snippet for chunk item reader and writer and the sql output for table lock.

Spring config file

<step id="filestep" xmlns="http://www.springframework.org/schema/batch" >
    <tasklet allow-start-if-complete="true" transaction-manager="ratransactionManager"  >
        <chunk writer="jdbcItenWriter" reader="fileItemReader" processor="itemProcessor" commit-interval="500" retry-limit="2">
         <retryable-exception-classes>
        <include class="org.springframework.dao.DeadlockLoserDataAccessException"/>
     </retryable-exception-classes>
    </chunk>
    <listeners>
        <listener ref="customStepExecutionListener">
        </listener>
    </listeners>
    </tasklet>
    <end on ="FAILED"/>
</step>

Oracle Locks

select
  object_name, 
  object_type, 
  session_id, 
  type,                 -- Type or system/user lock
  lmode,        -- lock mode in which session holds lock
  request, 
  block, 
  ctime,
  owner,
  id1,id2                 -- Time since current mode was granted
from
  v$locked_object, all_objects, v$lock 
where
  v$locked_object.object_id = all_objects.object_id AND
  v$lock.id1 = all_objects.object_id AND
  v$lock.sid = v$locked_object.session_id    
  and all_objects.OBJECT_NAME  like '%MSC%'
order by
  session_id, ctime desc, object_name


OBJECT_NAME         OBJECT_TYPE  SESSION_ID      TYPE LMODE  REQUEST  BLOCK  CTIME  OWNER  ID1      ID2                                    
STAGING_TABLE_MSC    TABLE        137            TM   3       0         0      39    CDRR  9289370  0

回答1:

LMODE 3 is just a row lock, probably from a normal insert, and shouldn't be a problem.

If you had seen LMODE 6 that would mean the entire table is exclusively locked. For example, from a direct-path write from an INSERT /*+APPEND*/.

See the V$LOCK documentation.

来源：https://stackoverflow.com/questions/8309975/table-lock-happens-for-spring-batch-chunk-item-reader-and-writer

标签

Oracle

oracle10g

spring-batch