## Bug Report <!-- Thanks for your bug report! Don't worry if you can't fill out all the sections. --> ### What version of TiKV are you using? <!-- You can run `tikv-server --version` --> ### What operating system and CPU are you using? <!-- If you're using Linux, you can run `cat /proc/cpuinfo` --> ### Steps to reproduce <!-- If possible, provide a recipe for reproducing the error. A complete runnable program is good. --> compare sysbench oltp_update_index workload with https://github.com/tikv/tikv/commit/b558d0bffc554c4c0094a483c65d95a50a4141cf and https://github.com/tikv/tikv/commit/126da29086da78bad3171975d4269ba283d133bd ### What did you expect? no performance degradation ### What did happened? commit b558d0 cause 7% ~ 14% performance degradation. 