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ASF GitHub Bot commented on DRILL-5899: --------------------------------------- Github user paul-rogers commented on the issue: https://github.com/apache/drill/pull/1015 Second long list of detailed comments sent privately to keep dev list traffic down. > Simple pattern matchers can work with DrillBuf directly > ------------------------------------------------------- > > Key: DRILL-5899 > URL: https://issues.apache.org/jira/browse/DRILL-5899 > Project: Apache Drill > Issue Type: Improvement > Components: Execution - Flow > Reporter: Padma Penumarthy > Assignee: Padma Penumarthy > Priority: Critical > > For the 4 simple patterns we have i.e. startsWith, endsWith, contains and > constant,, we do not need the overhead of charSequenceWrapper. We can work > with DrillBuf directly. This will save us from doing isAscii check and UTF8 > decoding for each row. > UTF-8 encoding ensures that no UTF-8 character is a prefix of any other valid > character. So, instead of decoding varChar from each row we are processing, > encode the patternString once during setup and do raw byte comparison. > Instead of bounds checking and reading one byte at a time, we get the whole > buffer in one shot and use that for comparison. > This improved overall performance for filter operator by around 20%. -- This message was sent by Atlassian JIRA (v6.4.14#64029)