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(for example, the write or update throughput is higher than 10 million lines/hours), due to the limited write capacity of network and physical disks, the I/O between TiKV and TiFlash becomes a bottleneck The datetime type can be used to store time values. • enum: The enum type can be used to store a limited selection of values. 4.5.3.5 Select primary key A primary key is a column or a set of columns in and network transmission. In most applications, SQL statements can be enumerated. You can use a limited number of SQL statements to complete data queries for the entire application. So using a prepared

(for example, the write or update throughput is higher than 10 million lines/hours), due to the limited write capacity of network and physical disks, the I/O between TiKV and TiFlash becomes a bottleneck The datetime type can be used to store time values. • enum: The enum type can be used to store a limited selection of values. 4.5.3.5 Select primary key A primary key is a column or a set of columns in and network transmission. In most applications, SQL statements can be enumerated. You can use a limited number of SQL statements to complete data queries for the entire application. So using a prepared

authenticated and authorized based on TiDB SQL users’ privileges. Therefore, TiDB Dashboard requires limited privileges, or merely the read-only privilege. You can configure users to access TiDB Dashboard based (for example, the write or update throughput is higher than 10 million lines/hours), due to the limited write capacity of network and physical disks, the I/O between TiKV and TiFlash becomes a bottleneck ms. P99 latency is around 50 ms. • Test result: When the total CPU utilization of the cluster is limited to 91%, the results are as follows: – The QPS of write workload reduced by 50%, and P99 latency

online. Support changing the column type online using the ALTER TABLE statement, including but not limited to: – Changing VARCHAR to BIGINT – Modifying the DECIMAL precision – Compressing the length of VARCHAR(10) scheduler-worker-pool- �→ size * 100%, or the CPU resources of the entire machine are relatively limited. If the write workload is large, check if [storage] scheduler-worker-pool-size is set too small. in v3.0.8 (#1986). • 5.3.2 PD OOM during the rolling upgrade. The size of gRPC messages is not limited, and the monitor shows that TCP InSegs is relatively large. This issue has been fixed in v3.0.6 (#1952)

key when BR performs encrypted backup #29794 – TiCDC * Reduce the count of “EventFeed retry rate limited” logs #4006 * Reduce the replication latency when replicating many tables #3900 * Reduce the time (for example, the write or update throughput is higher than 10 million lines/hours), due to the limited write capacity of network and physical disks, the I/O between TiKV and TiFlash becomes a bottleneck For clusters with hotspots, backup tasks on the TiKV node that has hotspots might be excessively limited, which slows down the overall backup process. – Solution: Eliminate the hotspot node, or disable

(for example, the write or update throughput is higher than 10 million lines/hours), due to the limited write capacity of network and physical disks, the I/O between TiKV and TiFlash becomes a bottleneck scheduler-worker-pool- �→ size * 100%, or the CPU resources of the entire machine are relatively limited. If the write workload is large, check if [storage] scheduler-worker-pool-size is set too small. in v3.0.8 (#1986). • 5.3.2 PD OOM during the rolling upgrade. The size of gRPC messages is not limited, and the monitor shows that TCP InSegs is relatively large. This issue has been fixed in v3.0.6 (#1952)

record in TiDB #49237 @zyguan Before v7.6.0, the size of a single row record in a transaction is limited by the TiDB configuration item txn-entry-size-limit. If the size limit is exceeded, TiDB returns (for example, the write or update throughput is higher than 10 million lines/hours), due to the limited write capacity of network and physical disks, the I/O between TiKV and TiFlash becomes a bottleneck The datetime type can be used to store time values. • enum: The enum type can be used to store a limited selection of values. 4.5.3.5 Select primary key A primary key is a column or a set of columns in

coarse. For example, it can only filter large granularity of DDL events such as ALTER. This method is limited in some scenarios. For example, the application allows ADD COLUMN but not DROP COLUMN, but they are refreshed every few minutes. This is unacceptable for some business scenarios where the cutover time is limited to tens of seconds. With the introduction of real-time updating of checkpoint for continuous data (for example, the write or update throughput is higher than 10 million lines/hours), due to the limited write capacity of network and physical disks, the I/O between TiKV and TiFlash becomes a bottleneck

joins, or �→ aggregations, can consume a significant amount of memory and have �→ previously been limited at very large scales. Bulk DML (tidb_ �→ dml_type = "bulk") is a new DML type for handling scheduling microservice: provides scheduling functions for the entire cluster, including but not limited to load balancing, hot spot handling, replica repair, and replica placement. Each microservice is machines with higher memory capacity to run the BR client. If the memory capacity of the machine is limited, it is recommended to use a finer-grained Region scattering algorithm. In addition, because the coarse-grained