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Sergey Shelukhin edited comment on HIVE-15743 at 1/31/17 7:09 PM: ------------------------------------------------------------------ does there have to be a string, as well as toCharArray? The original code has bytes as input. String creation is actually more than half of the cost of going from byte[] to double (see picture). Also, I am not sure how important the precision issue is; however, one thing to suggest, if it's rare and easy to detect, is to handle the 99% cases fast, and fall back to Double.parse(new String) in exotic/rare cases. was (Author: sershe): does there have to be a string, as well as toCharArray? The original code has bytes as input. String creation is actually more than half of the cost of going from byte[] to double (see picture). > vectorized text parsing: speed up double parse > ---------------------------------------------- > > Key: HIVE-15743 > URL: https://issues.apache.org/jira/browse/HIVE-15743 > Project: Hive > Issue Type: Bug > Reporter: Sergey Shelukhin > Assignee: Teddy Choi > Attachments: HIVE-15743.1.patch, HIVE-15743.2.patch, tpch-without.png > > > {noformat} > Double.parseDouble( > new String(bytes, fieldStart, fieldLength, > StandardCharsets.UTF_8));{noformat} > This takes ~25% of the query time in some cases. -- This message was sent by Atlassian JIRA (v6.3.15#6346)