wait_mutex duration reach 400ms when the number of total SST file reach 40 thousands

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### Expected behavior
Write duration and get duration should not be impacted so much by compaction.

### Actual behavior
The compaction impacts the Get duration and the Write duration a lot when the number of total SST files is about 40K. After we open the perf_context feature, we found the wait_mutex duration is very large, this is the root cause for the high latency.


### Steps to reproduce the behavior

- Set `target_file_size` = 8MB, and insert data to let the number of the total SST files reach about 40K
- Run read and write workload