tikv-in-memory-engine: Add link to config and extend docs

glossary.md

@@ -378,6 +378,10 @@
 
 [TiFlash](/tiflash/tiflash-overview.md) is a key component of TiDB's HTAP architecture. It is a columnar extension of TiKV that provides both strong consistency and good isolation. TiFlash maintains columnar replicas by asynchronously replicating data from TiKV using the **Raft Learner protocol**. For reads, it leverages the **Raft consensus index** and **MVCC (Multi-Version Concurrency Control)** to achieve **Snapshot Isolation** consistency. This architecture effectively addresses isolation and synchronization challenges in HTAP workloads, enabling efficient analytical queries while maintaining real-time data consistency.
 
+### TiKV MVCC In-Memory Engine (IME)
+
+[TiKV MVCC In-Memory Engine](/tikv-in-memory-engine.md) (IME) caches the latest written MVCC versions in memory and implements an MVCC GC mechanism independent of TiDB to accelerate queries involving a large number of MVCC historical versions.
+
 ### Timestamp Oracle (TSO)
 
 Because TiKV is a distributed storage system, it requires a global timing service, Timestamp Oracle (TSO), to assign a monotonically increasing timestamp. In TiKV, such a feature is provided by PD, and in Google [Spanner](http://static.googleusercontent.com/media/research.google.com/en//archive/spanner-osdi2012.pdf), this feature is provided by multiple atomic clocks and GPS. For more information, see [TSO](/tso.md).

grafana-tikv-dashboard.md

@@ -411,6 +411,35 @@
 - Blob GC output file size: The size of Titan GC output file
 - Blob GC file count: The count of blob files involved in Titan GC
 
+### In Memory Engine
+
+The following metrics are related to [TiKV MVCC In-Memory Engine](/tikv-in-memory-engine.md) (IME).
+
+- Ops: The number of operations per second for column families
+- Read MBps: The total bytes of read traffic in RocksDB and the in-memory engine
+- Coprocessor Handle duration: The time consumed for handling coprocessor requests
+- Region Cache Hit: The number of times data is successfully retrieved from the Region cache
+- Region Cache Hit Rate: The hit rate of Region cache
+- Region Cache Miss Reason: The reasons why data is not retrieved from the Region cache
+- Memory Usage: The memory usage of the in-memory engine
+- Region Count: The count of different types of Regions
+- GC Filter: The information about the filtering process during garbage collection (GC)
+- Region GC Duration: The time consumed for Region GC
+- Region Load Duration: The time consumed for loading Regions
+- Region Load Count: The number of Regions loaded per second
+- Region Eviction Duration: The time consumed for evicting Regions
+- Region Eviction Count: The number of Regions evicted per second
+- Write duration: The time consumed for write operations in the Region cache engine
+- 99% In-memory engine write duration per server: The 99th percentile of write duration per TiKV server for the in-memory engine
+- Prepare for write duration: The time consumed for preparing write operations in the in-memory engine
+- 99% In-memory engine prepare for write duration per server: The 99th percentile of time consumed for preparing write operations per TiKV server in the in-memory engine
+- Iterator operations: The number of different types of iterator operations
+- Seek duration: The time consumed for seek operations
+- Oldest Auto GC SafePoint: The oldest automatic GC safepoint for Regions cached in the in-memory engine
+- Newest Auto GC SafePoint: The newest automatic GC safepoint for Regions cached in the in-memory engine
+- Auto GC SafePoint Gap: The time gap between the newest automatic GC safepoint and the oldest automatic GC safepoint for Regions cached in the in-memory engine
+- Auto GC SafePoint Gap With TiKV: The gap between the TiKV automatic GC safepoint and the oldest automatic GC safepoint for Regions cached in the in-memory engine
+
 ### Pessimistic Locking
 
 - Lock Manager Thread CPU: The CPU utilization of the lock manager thread

tikv-in-memory-engine.md

@@ -32,7 +32,7 @@ The preceding diagram shows two rows of records, each with 9 MVCC versions. The
 
 ## Usage
 
-To enable the TiKV MVCC in-memory engine (IME), you need to adjust the TiKV configuration and restart TiKV. The configuration details are as follows:
+To enable the TiKV MVCC in-memory engine (IME), you need to adjust the [TiKV configuration](/tikv-configuration-file.md#in-memory-engine-new-in-v850) and restart TiKV. The configuration details are as follows:
 
 ```toml
 [in-memory-engine]
@@ -133,3 +133,31 @@ The following result shows that queries with severe MVCC amplification exist on
 +----------------------------+-----+-------------------+--------------+------------+-----------------------------------+--------------------+--------------------+--------------------+
 5 rows in set (1.26 sec)
 ```
+
+### How can I check whether the TiKV MVCC in-memory engine is enabled?
+
+You can check the TiKV configuration using the [`SHOW CONFIG`](/sql-statements/sql-statement-show-config.md) statement. If the value of `in-memory-engine.enable` is `true`, it means that TiKV MVCC in-memory engine is enabled.
+
+```sql
+SHOW CONFIG WHERE Type='tikv' AND Name LIKE 'in-memory-engine\.%';
+```
+
+```
++------+-----------------+-----------------------------------------------+---------+
+| Type | Instance        | Name                                          | Value   |
++------+-----------------+-----------------------------------------------+---------+
+| tikv | 127.0.0.1:20160 | in-memory-engine.capacity                     | 5GiB    |
+| tikv | 127.0.0.1:20160 | in-memory-engine.cross-check-interval         | 0s      |
+| tikv | 127.0.0.1:20160 | in-memory-engine.enable                       | true    |
+| tikv | 127.0.0.1:20160 | in-memory-engine.evict-threshold              | 4920MiB |
+| tikv | 127.0.0.1:20160 | in-memory-engine.gc-run-interval              | 3m      |
+| tikv | 127.0.0.1:20160 | in-memory-engine.load-evict-interval          | 5m      |
+| tikv | 127.0.0.1:20160 | in-memory-engine.mvcc-amplification-threshold | 10      |
+| tikv | 127.0.0.1:20160 | in-memory-engine.stop-load-threshold          | 4208MiB |
++------+-----------------+-----------------------------------------------+---------+
+8 rows in set (0.00 sec)
+```
+
+### How can I monitor the TiKV MVCC in-memory engine?
+
+You can check the [**In Memory Engine**](/grafana-tikv-dashboard.md#in-memory-engine) section on the TiKV-Details dashboard in Grafana.