After the merge is completed, replace the file and rebuild the index from disk.
Advantages: Memory usage does not increase.
Disadvantages: The whole process requires a write lock, and the db cannot be read or written externally.
Put the written index data into the temporary storage area during the merge process (like copy-on-write), and build an index while building the hint file. When the merge ends, the index of the temporary storage area and the hint index to combine.
Advantages: DB's write lock time is smooth and can be merged smoothly.
Disadvantage: There may be more than twice the memory overhead.
Based on the shortcomings of bitcase, I chose the first option.
I have two ideas for this function:
After the merge is completed, replace the file and rebuild the index from disk. Advantages: Memory usage does not increase. Disadvantages: The whole process requires a write lock, and the db cannot be read or written externally.
Put the written index data into the temporary storage area during the merge process (like copy-on-write), and build an index while building the hint file. When the merge ends, the index of the temporary storage area and the hint index to combine. Advantages: DB's write lock time is smooth and can be merged smoothly. Disadvantage: There may be more than twice the memory overhead.
Based on the shortcomings of bitcase, I chose the first option.