1Z0-997-25 Question 93
Single answerYou are designing a high-traffic e-commerce application on Oracle Cloud Infrastructure (OCI). A major bottleneck is frequent reads on product catalog data stored in an Oracle Autonomous Database, causing increased latency. To address this, you plan to leverage OCI Cache to reduce database load and improve overall response times. Which approach is most appropriate for optimizing performance and maintaining data consistency in this scenario?
- A
Store the product catalog data in OCI Cache with a write-back pattern, updating the database only upon item eviction.
- B
Implement a read-through strategy in OCI Cache that retrieves data from the database on a cache miss and refreshes stale entries on a fixed schedule.
- C
Configure OCI Cache to replicate data across multiple regions synchronously, using global transactions for write operations.
- D
Implement a near-cache strategy on each application server, backed by OCI Cache, combined with a write-through pattern for updates.
Show answer and explanation
Correct answer: D
Explanation
Near-caching combined with a write-through pattern is a widely recommended approach in OCI for high-read, moderate-write applications. It balances performance gains from caching with minimal data staleness. Each application server caches data locally (reducing network latency), while the write-through pattern immediately commits updates to both the cache and the database. This ensures that the system avoids stale data issues while providing quick response times. For more details on implementing caching best practices in OCI, refer to the Oracle Cloud Infrastructure documentation on caching strategies and distributed caching patterns.
- A. Incorrect.
Option 1: This approach (write-back) defers writes to the database until the cache item is evicted. While it might reduce immediate database load, it risks data loss and inconsistencies if the cache node fails before eviction. Hence, it is not ideal for product catalog data where data consistency is critical.
- B. Incorrect.
Option 2: A read-through cache with a fixed refresh schedule can reduce database reads, but stale data may linger if updates happen between refresh intervals. In a high-traffic e-commerce environment, ensuring timely updates is vital, making this approach prone to outdated product information.
- C. Incorrect.
Option 3: Synchronous multi-region replication for all cache writes can significantly increase write latency, defeating performance gains from caching. It also introduces complexity in managing distributed global transactions, which is typically excessive for frequently accessed catalog data.
- D. Correct.
Option 4: A near-cache strategy places frequently accessed data in memory on each application server, reducing network hops. Backing it with OCI Cache ensures consistent data across the application nodes. Using a write-through pattern means every write first updates the cache and immediately writes to the database, preserving data integrity and reducing stale entries.