performance: remove tidb_enable_batch_dml (#19633) (#19642)

tidb-performance-tuning-config.md

@@ -311,7 +311,6 @@ The following sections explain how to handle each of these cases. You need to ad
 If your workload involves frequent small transactions or queries that frequently request timestamps, TSO (Timestamp Oracle) can become a performance bottleneck. To check if TSO wait time is impacting your system, check the [**Performance Overview > SQL Execute Time Overview**](/grafana-performance-overview-dashboard.md#sql-execute-time-overview) panel. If TSO wait time constitutes a large portion of your SQL execution time, consider the following optimizations:
 
 - Use low-precision TSO (enable [`tidb_low_resolution_tso`](/system-variables.md#tidb_low_resolution_tso)) for read operations that do not need strict consistency. For more information, see [Solution 1: use low-precision TSO](#solution-1-low-precision-tso).
-- Enable [`tidb_enable_batch_dml`](/system-variables.md#tidb_enable_batch_dml) to reduce TSO requests for batch operations
 - Combine small transactions into larger ones where possible. For more information, see [Solution 2: parallel mode for TSO requests](#solution-2-parallel-mode-for-tso-requests).
 
 #### Solution 1: low-precision TSO