Jim Apple has posted comments on this change.

Change subject: IMPALA-5273: Replace StringCompare with glibc memcmp
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Patch Set 2:

(2 comments)

http://gerrit.cloudera.org:8080/#/c/6768/1//COMMIT_MSG
Commit Message:

PS1, Line 17:  (repeat("a", 2048));
> Alternatively, you could run any other benchmark that gives more comprehens
I ran, in addition bin/run-workload and 
tests/benchmark/report_benchmark_results.py on TPC-H, TPC-DS, and 
targeted-perf, scale factor 10, on a single machine with a query_iterations 
setting of 10 on parquet/none. One query had significantly different times, and 
it showed an improvement with this patch: PERF_AGG-Q3. I reran it with 200 
repetitions to be more confident and I reproduced the result. The improvement 
was 21%.


http://gerrit.cloudera.org:8080/#/c/6768/2/be/src/runtime/string-value.inline.h
File be/src/runtime/string-value.inline.h:

PS2, Line 40: memcmp
> why not strncmp()? oh, I guess memcmp() is faster since it doesn't need to 
Exactly


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Gerrit-MessageType: comment
Gerrit-Change-Id: Ie4786a4a75fdaffedd6e17cf076b5368ba4b4e3e
Gerrit-PatchSet: 2
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Jim Apple <[email protected]>
Gerrit-Reviewer: Dan Hecht <[email protected]>
Gerrit-Reviewer: Jim Apple <[email protected]>
Gerrit-Reviewer: Mostafa Mokhtar <[email protected]>
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