Note:
This topic has been translated from a Chinese forum by GPT and might contain errors.Original topic: br备份限速问题
[TiDB Usage Environment] Production Environment / Testing / PoC
[TiDB Version]
[Reproduction Path] What operations were performed when the issue occurred
[Encountered Issue: Issue Phenomenon and Impact]
[Resource Configuration] Enter TiDB Dashboard - Cluster Info - Hosts and take a screenshot of this page
[Attachments: Screenshots / Logs / Monitoring]
Documentation:
Use the --ratelimit parameter to limit the speed of backup tasks. Note that this parameter limits the speed at which backup files are stored to external storage. When calculating the size of the backup file, please refer to the backup data size (after compressed) in the backup log. After setting --ratelimit, to avoid the failure of rate limiting due to too many tasks, the concurrency parameter of br will be automatically adjusted to 1.
Issue:
The ratelimit restricts the maximum speed, and the concurrency parameter of br will be automatically adjusted to 1. In actual observation, during the backup period, 90% of the traffic is very low, far below the ratelimit value, resulting in a very long backup time.
During the backup window, it is actually permissible to run for a long time under the ratelimit traffic load. After limiting the speed and automatically adjusting the concurrency to 1, the backup cannot be completed within the backup window.
Is there a good way to both limit the speed and shorten the backup time?