pkg/lightning : remove get_regions call in physical backend (#46202) #46334
+136
−4
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This is an automated cherry-pick of #46202
What problem does this PR solve?
Problem Summary:
When lightning runs in physical import mode, it runs this sql query
SELECT REGION_ID, APPROXIMATE_SIZE FROM information_schema.TIKV_REGION_STATUS WHERE TABLE_ID = ?
This call is made by each lightning process in parallel import mode and by multiple worker threads in a lightning process. It can potentially overload the PD if number of regions are too many. However, it appears that this call may be unnecessary since its purpose is to display a warning message and increment a counter in the SplitAndScatterRegionByRanges() function. Considering that lightning physical import always operates on a new table, splitting the new region should not pose any harm.
Issue Number: close #45507
What is changed and how it works?
Remove the getRegions call from lightning
Check List
Tests
Release note
We saw this issue in 6.5.0
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