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Todd Lipcon commented on KUDU-2847: ----------------------------------- After optimizing predicate evaluation (KUDU-2846) this is now about 20% of the scanner thread CPU for TPCH Q6 > Optimize iteration over selection vector in SerializeRowBlock > ------------------------------------------------------------- > > Key: KUDU-2847 > URL: https://issues.apache.org/jira/browse/KUDU-2847 > Project: Kudu > Issue Type: Improvement > Components: perf, tserver > Reporter: Todd Lipcon > Priority: Major > > Currently, SerializeRowBlock operates column-by-column, which means we have > to iterate over the selection bitmap once for each column. This code isn't > particularly well optimized -- in TPCH Q6, about 10% of CPU is spent in > BitmapFindFirst. We should look at alternate implementations here that better > amortize the bitmap iteration cost across all of the columns and generally > micro-optimize it. -- This message was sent by Atlassian JIRA (v7.6.3#76005)