# Case Study: Deleting Large Amount of Data (Continue...)

+ **`Granfana > tikv-details > rocksdbkv > Compaction reason`**
  + Manual compaction
    + Manual compaction by **`tikv-ctl`** (online)
    + Compaction by `TiKV` auto check thread
      + **`region-compact-check-interval`** (10 mins)
      + **`region-compact-tombstones-percent`** (30%)
      + **`region-compact-check-step`** (100)
  + **`levelL0FilesNum`** （level0-file-num-compaction-trigger）
  + **`BottommostFiles`**
    + When snapshot released, check the tombstones in bottommost files

![`smart`](CompactionReason_aa_001_20221029.png)

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Because RawKV's MVCC is RocksDB based, when deleting large amount of data, in addition to deleting files directly by `DeleteRange`, the primary workload is on the compaction side, so this slide focuses on common compaction triggering `reasons` and available parameters for tuning.

Manually compact data for `TiKV`: `https://docs.pingcap.com/tidb/dev/tikv-control#compact-data-of-each-tikv-manually`

`region-compact-check-interval`: `https://docs.pingcap.com/tidb/stable/tikv-configuration-file#region-compact-check-interval`

`region-compact-tombstones-percent`: `https://docs.pingcap.com/tidb/stable/tikv-configuration-file#region-compact-tombstones-percent`

`region-compact-check-step`: `https://docs.pingcap.com/tidb/stable/tikv-configuration-file#region-compact-check-step`

`levelL0FilesNum`: `https://docs.pingcap.com/tidb/stable/tikv-configuration-file#level0-file-num-compaction-trigger`