In earlier releases, the MAXTRANS parameter determined the maximum number of concurrent update transactions allowed for each data block in the segment. This parameter has been deprecated. Oracle now automatically allows up to 255 concurrent update transactions for any data block, depending on the available space in the block.
Existing objects for which a value of MAXTRANS has already been set retain that setting. However, if you attempt to change the value for MAXTRANS, Oracle ignores the new specification and substitutes the value 255 without returning an error.
对于ini_trans, max_trans的默认值,表级为1,索引级为2. 一般来说不需要做特别的设置。可以根据业务的需要来配置。
以下设置可供参考:
对于大表,数据千万级以上的表,initrans建议设置为8~16
对于中级表,数据量在百万到千万级,initrans建议设置为4~8
对于普通的表,initrans建议设置为1~4
对于此等待事件,解决思路有三种:
1) Depending on the number of transactions in the table we need to alter the value of INITRANS.
If the issue is not resolved by increasing INITRANS then try increasing PCTFREE. Increasing PCTFREE holds more
1) Spreading rows into more number of blocks will also helps to reduce this wait event.
2) Then re-organize the table using move (alter table service_T move;)
3) Rebuild index
Increase INITRANS
here it has been changed to 50:
2) Then re-organize the table using move (alter table move;)
3) Then rebuild all the indexes of this table as below
Increase PCTFREE
space back and so spreads the same number of rows over more blocks. This means that there are more ITL slots
available overall :
A Combination of increasing both INITRANS and PCTFREE
1) Set INITRANS to 50 pct_free to 40
2) Re-organize the table using move (alter table move;)
3) Then rebuild all the indexes of the table as below
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