What are the main difficulties that can arise when processing one thousand transactions in parallel?

When processing thousands of transactions in parallel, the following main difficulties may arise:

• Race Conditions: multiple threads may attempt to modify the same data simultaneously, leading to inconsistency.
• Deadlocks: improper synchronization management can result in a situation where threads wait for each other indefinitely.
• Performance issues: an excessive number of threads can lead to context switching and a decrease in overall performance.
• Transaction management: it is necessary to ensure atomicity, consistency, isolation, and durability (ACID), which is challenging in parallel processing.
• Error handling and rollback: in case of a transaction failure, changes need to be correctly rolled back without affecting others.

To address these problems, synchronization mechanisms, thread pools, transaction managers, and optimistic/pessimistic locking are often used.