docs: add config "raftstore.appy-yield-msg-size" (#11083)

dynamic-config.md

@@ -153,6 +153,7 @@ The following TiKV configuration items can be modified online:
 | `raftstore.merge-check-tick-interval` | The time interval for merge check |
 | `raftstore.cleanup-import-sst-interval` | The time interval to check expired SST files |
 | `raftstore.local-read-batch-size` | The maximum number of read requests processed in one batch |
+| `raftstore.apply-yield-write-size` | The maximum number of bytes that the Apply thread can write for one FSM (Finite-state Machine) in each round |
 | `raftstore.hibernate-timeout` | The shortest wait duration before entering hibernation upon start. Within this duration, TiKV does not hibernate (not released). |
 | `raftstore.apply-pool-size` | The number of threads in the pool that flushes data to the disk, which is the size of the Apply thread pool |
 | `raftstore.store-pool-size` | The number of threads in the pool that processes Raft, which is the size of the Raftstore thread pool |

tikv-configuration-file.md

@@ -818,6 +818,13 @@ Configuration items related to Raftstore.
 + Default value: `1024`
 + Minimum value: greater than `0`
 
+### `apply-yield-write-size` <span class="version-mark">New in v6.4.0</span>
+
++ The maximum number of bytes that the Apply thread can write for one FSM (Finite-state Machine) in one round of poll. This is a soft limit.
++ Default value: `"32KiB"`
++ Minimum value: greater than `0`
++ Unit: KiB|MiB|GiB
+
 ### `apply-max-batch-size`
 
 + Raft state machines process data write requests in batches by the BatchSystem. This configuration item specifies the maximum number of Raft state machines that can process the requests in one batch.