ti-chi-bot
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1 year ago [REVIEW NOTIFICATION]
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- zhangyangyu
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shiyuhang0
What problem does this PR solve?
Support probe TiFlash status.
When you have two TiFlash and suspend one during the job, the suspended TiFlash can still be chosen and the request to it will wait for a timeout for grpc. It wastes resources and affected the whole job's speed.
What is changed and how it works?
When we choose the TiFlash. we call the isalive to probe the status of TiFlash. If it is not ready, drop the task.
Alternatives
In this pr, a background thread poll will refresh the cache of TiFlash store status every time a region task has been generated. Then drop the task whose store is unavailable. The cons are if there are many tasks, the thread poll will be distributed too much probe tasks.
Another way is to use a corn job to refresh the cache: