The size of BatchScanRegionsRequest might exceed the default MaxRequestBytes #1704
Description
The size of BatchScanRegionsRequest might exceed the default MaxRequestBytes (150MiB) when there are a lot of key ranges waiting for scan. The related messages are shown as the following.
grpc:received message larger than max(297800997 vs 157810688)
pdrpc backoffer.maxsleep 20000ms is exceeded,errors:batchScanRegion from PD failed,range num:1059860,limit:128