Oracle's row level locking implementation achieves a high-degree of scalability by maintaining lists of row level locks in each data block rather than in some centralized data structure. This list is called ITL (interested transaction list).
ITL depends upon following create table parameter.
1. INITRANS --> No of entries that will be available in each block when first created.
2. PCTFREE ---> Keeps some room in the block free for rows to grow when updated and also for the ITL to grow.
3. MAXTRANS --->Setting the very low value of MAXTRANS will have the same effect as setting very low value of PCTFREE.
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