1.3 KiB
1.3 KiB
Simple Compaction Strategy
In this chapter, you will:
- Implement a simple leveled compaction strategy and simulate it on the compaction simulator.
- Start compaction as a background task and implement a compaction trigger in the system.
Task 1: Simple Level Compaction
Task 2: Compaction Simulation
Task 3: Integrate with the Read Path
Test Your Understanding
- Is it correct that a key will only be purged from the LSM tree if the user requests to delete it and it has been compacted in the bottom-most level?
- Is it a good strategy to periodically do a full compaction on the LSM tree? Why or why not?
- Actively choosing some old files/levels to compact even if they do not violate the level amplifier would be a good choice, is it true? (Look at the Lethe paper!)
- If the storage device can achieve a sustainable 1GB/s write throughput and the write amplification of the LSM tree is 10x, how much throughput can the user get from the LSM key-value interfaces?
- What is your favorite boba shop in your city? (If you answered yes in week 1 day 3...)
We do not provide reference answers to the questions, and feel free to discuss about them in the Discord community.
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