condition in table creation, reduced durability & fault tolerance in fresh clusters, and several crashes on startup. With both auto-retry mechanisms disabled, TiDB 2.1.8 through 3.0.0-beta.1-40 passed our detection strategy are somewhat involved, and will be published in an upcoming paper. 3 3 Results 3.1 Crashes on Startup When their connection to Placement Driver is lost, TiKV nodes try indefinitely to reconnect it will only try to connect a finite number of times, and if those at- tempts fail, the process crashes.2 In 2.1.7 through 3.0.0-beta.1, restarting every process could (depending on the state of KV & PD

cluster to the secondary relational database TiDB/Aurora/MySQL/MariaDB. In case the primary cluster crashes, TiCDC can recover the secondary cluster to a certain snapshot in the primary cluster within 5 minutes the worker-count parameter of Drainer. 11.7.15.7 What can I do if a Pump instance crashes? If a Pump instance crashes, Drainer cannot replicate data to the downstream because it cannot obtain the data TiDB-backend. 11.8.3.1 Notes Before starting TiDB Lightning, note that: 1078 • If tidb-lightning crashes, the cluster is left in “import mode”. Forgetting to switch back to “normal mode” can lead to a high

lose some row changes during table renaming #43338 @tangenta • Fix the issue that TiDB server crashes when the client uses cursor reads #38116 @YangKeao • Fix the issue that ADMIN SHOW DDL JOBS LIMIT @JaySon-Huang • Tools • Backup & Restore (BR) 84 • Fix the issue of backup slowdown when a TiKV node crashes in a cluster #42973 @YuJuncen • Fix the issue of inaccurate error messages caused by a backup failure #8877 @asddongmen • Fix the issue that checkpoint lag increases when one of the upstream TiKV nodes crashes #8858 @hicqu • Fix the issue that when replicating data to object storage, the EXCHANGE �→ PARTITION

tidb_enable_collect_execution_info causes the coprocessor cache to panic #48212 @you06 • Fix the issue that TiDB crashes when shuffleExec quits unexpectedly #48230 @wshwsh12 • Fix the issue that static CALIBRATE RESOURCE import task can be resumed from the latest checkpoint upon restart. If the TiDB Lightning task crashes due to unrecoverable errors (for example, data cor- ruption), it will not pick up from the checkpoint Top SQL cannot be used to pinpoint non-performance issues, such as incorrect data or abnormal crashes. The Top SQL feature is still in an early stage and is being continuously enhanced. Here are some

import task can be resumed from the latest checkpoint upon restart. If the TiDB Lightning task crashes due to unrecoverable errors (for example, data cor- ruption), it will not pick up from the checkpoint Top SQL cannot be used to pinpoint non-performance issues, such as incorrect data or abnormal crashes. The Top SQL feature is still in an early stage and is being continuously enhanced. Here are some upstream MySQL instance that DM-worker connects to needs downtime main- tenance or when the instance crashes unexpectedly, you need to switch the DM-worker connection to another MySQL instance within the same

that the TestStoreRemoved test case is unstable #52791 @YuJuncen • Fix the issue that TiFlash crashes during point-in-time recovery (PITR) #52628 @RidRisR • Fix the inefficiency issue in scanning DDL recommended to use cloud disks for TiKV nodes. Data on local disks might be lost if the TiKV instance crashes in the cloud environment. Before you deploy TiFlash, note the following items: • TiFlash can be import task can be resumed from the latest checkpoint upon restart. If the TiDB Lightning task crashes due to unrecoverable errors (for example, data cor- ruption), it will not pick up from the checkpoint

TiFlash needs to create when processing disag- gregated storage and compute requests, helping avoid crashes of TiFlash compute nodes when processing a large number of such requests #9334 @JinheLin • Enhance recommended to use cloud disks for TiKV nodes. Data on local disks might be lost if the TiKV instance crashes in the cloud environment. 702 Before you deploy TiFlash, note the following items: • TiFlash can import task can be resumed from the latest checkpoint upon restart. If the TiDB Lightning task crashes due to unrecoverable errors (for example, data cor- ruption), it will not pick up from the checkpoint

recommended to use cloud disks for TiKV nodes. Data on local disks might be lost if the TiKV instance crashes in the cloud environment. Before you deploy TiFlash, note the following items: • TiFlash can be import task can be resumed from the latest checkpoint upon restart. If the TiDB Lightning task crashes due to unrecoverable errors (for example, data cor- ruption), it will not pick up from the checkpoint Top SQL cannot be used to pinpoint non-performance issues, such as incorrect data or abnormal crashes. The Top SQL feature is still in an early stage and is being continuously enhanced. Here are some

TiFlash needs to create when processing disag- gregated storage and compute requests, helping avoid crashes of TiFlash compute nodes when processing a large number of such requests #9334 @JinheLin • Enhance to use cloud disks for TiKV nodes. Data 697 on local disks might be lost if the TiKV instance crashes in the cloud environment. Before you deploy TiFlash, note the following items: • TiFlash can be import task can be resumed from the latest checkpoint upon restart. If the TiDB Lightning task crashes due to unrecoverable errors (for example, data cor- ruption), it will not pick up from the checkpoint

recommended to use cloud disks for TiKV nodes. Data on local disks might be lost if the TiKV instance crashes in the cloud environment. Before you deploy TiFlash, note the following items: • TiFlash can be import task can be resumed from the latest checkpoint upon restart. If the TiDB Lightning task crashes due to unrecoverable errors (for example, data cor- ruption), it will not pick up from the checkpoint Top SQL cannot be used to pinpoint non-performance issues, such as incorrect data or abnormal crashes. The Top SQL feature is still in an early stage and is being continuously enhanced. Here are some