Support setting memory usage limits for in-memory pessimistic locks in a Region or TiKV instance. When hot write scenarios cause a large number of pessimistic locks, you can increase the memory limits via configuration to scatter-range-scheduler in pd-ctl commands #8379 @okJiang • Add conflict detection for grant-hot-leader-scheduler #4903 @lhy1024 • TiFlash • Optimize the execution efficiency of LENGTH() and ASCII() application workload patterns, you might need to change the table schema to avoid transaction contention or hot spots. 4.10.1.1 SQL performance tuning To get good SQL statement performance, you can follow these

Support setting memory usage limits for in-memory pessimistic locks in a Region or TiKV instance. When hot write scenarios cause a large number of pessimistic locks, you can increase the memory limits via configuration to scatter-range-scheduler in pd-ctl commands #8379 @okJiang • Add conflict detection for grant-hot-leader-scheduler #4903 @lhy1024 • TiFlash • Optimize the execution efficiency of LENGTH() and ASCII() application workload patterns, you might need to change the table schema to avoid transaction contention or hot spots. 4.10.1.1 SQL performance tuning To get good SQL statement performance, you can follow these

application workload patterns, you might need to change the table schema to avoid transaction contention or hot spots. 4.9.1.1 SQL performance tuning To get good SQL statement performance, you can follow these diagnose and resolve transaction contention, see Troubleshoot Lock Conflicts. • Hot spots. For how to diagnose and resolve hot spots, see Troubleshoot Hotspot Issues. 4.9.1.2.1 See also • SQL Performance null �→ | null | null | | 001Do000003EDTZIA4 | Edge Communications | Customer - Direct | TX �→ | Hot | Electronics | | 001Do000003EDTaIAO | Burlington Textiles Corp of America | Customer - �→ Direct

performance of Region heartbeat processing #7897 @nolouch @rleungx @JmPotato • pd-ctl supports querying hot Regions by the byte or query dimension #7369 @lhy1024 • TiFlash • Reduce lock conflicts under highly application workload patterns, you might need to change the table schema to avoid transaction contention or hot spots. 4.9.1.1 SQL performance tuning To get good SQL statement performance, you can follow these diagnose and resolve transaction contention, see Troubleshoot Lock Conflicts. • Hot spots. For how to diagnose and resolve hot spots, see Troubleshoot Hotspot Issues. 4.9.1.2.1 See also • SQL Performance

incorrect when executing EXPLAIN ANALYZE #52646 @JaySon-Huang • Fix the issue that querying the TIDB_HOT_REGIONS table might incorrectly return INFORMATION_SCHEMA tables #50810 @Defined2014 • Fix the issue application workload patterns, you might need to change the table schema to avoid transaction contention or hot spots. 4.9.1.1 SQL performance tuning To get good SQL statement performance, you can follow these diagnose and resolve transaction contention, see Troubleshoot Lock Conflicts. • Hot spots. For how to diagnose and resolve hot spots, see Troubleshoot Hotspot Issues. 4.9.1.2.1 See also • SQL Performance

#7853 @okJiang – 在 pd-ctl 命令中将 scatter-range 重命名为 scatter-range-scheduler #8379 @okJiang – 为 grant-hot-leader-scheduler 添加冲突检测 #4903 @lhy1024 • TiFlash – 优化 LENGTH() 和 ASCII() 函数执行效率 #9344 @xzhangxian1008 c12f /data1 ext4 defaults,nodelalloc,noatime 0 2 6. 挂载数据盘。 mkdir /data1 && \ systemctl daemon-reload && \ mount -a 7. 执行以下命令，如果文件系统为 ext4，并且挂载参数中包含 nodelalloc，则表示已生效。 mount -t ext4 /dev/nvme0n1p1 op" 6. 应用 udev 脚本。 注意： 对于已经使用 noop 或 none I/O 调度器的设备，无需配置 udev 规则，可以跳过此步 骤。 udevadm control --reload-rules udevadm trigger --type=devices --action=change 7. 创建 CPU 节能策略配置服务。 cat >> /etc/systemd/system/cpupower

#7853 @okJiang – 在 pd-ctl 命令中将 scatter-range 重命名为 scatter-range-scheduler #8379 @okJiang – 为 grant-hot-leader-scheduler 添加冲突检测 #4903 @lhy1024 • TiFlash – 优化 LENGTH() 和 ASCII() 函数执行效率 #9344 @xzhangxian1008 c12f /data1 ext4 defaults,nodelalloc,noatime 0 2 6. 挂载数据盘。 mkdir /data1 && \ systemctl daemon-reload && \ mount -a 7. 执行以下命令，如果文件系统为 ext4，并且挂载参数中包含 nodelalloc，则表示已生效。 mount -t ext4 /dev/nvme0n1p1 op" 6. 应用 udev 脚本。 注意： 对于已经使用 noop 或 none I/O 调度器的设备，无需配置 udev 规则，可以跳过此步 骤。 udevadm control --reload-rules udevadm trigger --type=devices --action=change 7. 创建 CPU 节能策略配置服务。 cat >> /etc/systemd/system/cpupower

/data1 ext4 defaults,nodelalloc,noatime 0 2 460 6. 挂载数据盘。 mkdir /data1 && \ systemctl daemon-reload && \ mount -a 7. 执行以下命令，如果文件系统为 ext4，并且挂载参数中包含 nodelalloc，则表示已生效。 mount -t ext4 /dev/nvme0n1p1 op" 6. 应用 udev 脚本。 注意： 对于已经使用 noop 或 none I/O 调度器的设备，无需配置 udev 规则，可以跳过此步 骤。 udevadm control --reload-rules udevadm trigger --type=devices --action=change 7. 创建 CPU 节能策略配置服务。 cat >> /etc/systemd/system/cpupower --governor performance [Install] WantedBy=multi-user.target EOF 8. 应用 CPU 节能策略配置服务。 systemctl daemon-reload systemctl enable cpupower.service systemctl start cpupower.service 6. 执行以下命令验证透明大页的状态。 cat /

. 148 9.4.2 Guest graphics and mouse driver setup in depth . . . . . . . . . . . . . 148 9.5 CPU hot-plugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 9.6 PCI passthrough running modern server operating systems, VirtualBox also supports CPU hot-plugging. For details about this, please refer to chapter 9.5, CPU hot-plugging, page 149. 3.4.3 “Acceleration” tab On this page, you number of virtual CPUs for the virtual machine (see chapter 3.4.2, “Processor” tab, page 48). If CPU hot-plugging is enabled (see below), this then sets the maximum number of virtual CPUs that can be plugged

. 157 9.4.2 Guest graphics and mouse driver setup in depth . . . . . . . . . . . . . 157 9.5 CPU hot-plugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 9.6 PCI passthrough running modern server operating systems, VirtualBox also supports CPU hot-plugging. For details about this, please refer to chapter 9.5, CPU hot-plugging, page 158. 3.4.3 “Acceleration” tab On this page, you number of virtual CPUs for the virtual machine (see chapter 3.4.2, “Processor” tab, page 49). If CPU hot-plugging is enabled (see below), this then sets the maximum number of virtual CPUs that can be plugged