to protect against big scan, we set hbase.server.scanner.max.result.size = 10MB in our customer hbase cluster, however our clients can meet MultiActionResultTooLarge even in small batch get (for ex. 15 batch get, and row size is about 5KB ) .
after HBASE-14978 hbase take the data block reference into consideration, but the block size is 64KB (the default value ), even if all cells are from different block , the block size retained is less than 1MB, so what's the problem ?
finally i found that
HBASE-14978 also consider the cell in memstore, as MSLAB is enabled default, so if the cell is from memstore, cell backend array can be large (2MB as default), so even if a small batch can meet this error, is this reasonable ?
when throw MultiActionResultTooLarge exception, hbase client should retry ignore rpc retry num, however if set retry num to zero, client will fail without retry in this case.
see attachment TestMultiRespectsLimitsMemstore for details.