Eyal Allweil created PIG-4803:
---------------------------------

             Summary: Improve performance of regex-based builtin functions
                 Key: PIG-4803
                 URL: https://issues.apache.org/jira/browse/PIG-4803
             Project: Pig
          Issue Type: Improvement
            Reporter: Eyal Allweil


There are three strategies used by Pig's regex-based built in functions.

1) REPLACE doesn't do any pattern caching.

2) REGEX_EXTRACT and REGEX_EXTRACT_ALL attempt to cache a single pattern as an 
instance variable.

3) PluckTuple attempts to cache a single pattern statically. (doesn't this 
cause problems if two clashing defines for different PluckTuples are used?)

I have a little fix and a medium fix in mind. The little fix is to give REPLACE 
a similar caching strategy, and to fix PluckTuple, if the static nature of the 
pattern is indeed a problem.

The medium fix is to make all four functions take an additional constructor 
with a constant regex (and therefore one less argument in evaluation) and use 
that if it exists. This would be backwards compatible, should barely (or not) 
affect the performance of the existing code path, but I think that in cases 
where there are two clashing usages of the functions in the same 
foreach..generate it would allow the pattern caching to work.




--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to