Hello Dan Hecht, I'd like you to reexamine a change. Please visit
http://gerrit.cloudera.org:8080/7303 to look at the new patch set (#6). Change subject: IMPALA-5560: always store CHAR(N) inline in tuple ...................................................................... IMPALA-5560: always store CHAR(N) inline in tuple This is done to simplify the CHAR(N) logic. I believe this is overall an improvement - any benefits of the out-of-line storage that motivated this optimisation originally were outweighed by the added complexity. This also avoids IMPALA-5559 (fe/be have different notions of var-len), which will unblock IMPALA-3200. Pros: * Reduce the number of code paths and improve test coverage. (e.g. avoids IMPALA-5559: fe/be have different notions of var-len) * Reduced memory to store non-NULL data (saves 12-byte StringValue) * Fewer branches in code -> save CPU cycles. * If CHAR(N) performance is important, reduced complexity makes it easier to implement codegen. Cons: * Requires N bytes to store a NULL value. * May hurt cache locality (although this is speculative in my mind). The change is mostly mechanical - I removed MAX_CHAR_INLINE_LENGTH and then removed branches that depended on that. Testing: Ran exhaustive build. Change-Id: I9c0b823ccff6b0c37f5267c548d096c29b8caac3 --- M be/src/exec/hash-table.cc M be/src/exec/hdfs-avro-scanner-test.cc M be/src/exec/hdfs-parquet-table-writer.cc M be/src/exec/hdfs-text-table-writer.cc M be/src/exec/parquet-column-readers.cc M be/src/exprs/agg-fn-evaluator.cc M be/src/exprs/anyval-util.h M be/src/exprs/scalar-expr-evaluator.cc M be/src/exprs/slot-ref.cc M be/src/runtime/raw-value-ir.cc M be/src/runtime/raw-value.cc M be/src/runtime/raw-value.inline.h M be/src/runtime/string-value.h M be/src/runtime/string-value.inline.h M be/src/runtime/types.h M be/src/service/fe-support.cc M be/src/service/hs2-util.cc M fe/src/main/java/org/apache/impala/catalog/ScalarType.java M testdata/workloads/functional-query/queries/QueryTest/spilling.test 19 files changed, 69 insertions(+), 130 deletions(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/03/7303/6 -- To view, visit http://gerrit.cloudera.org:8080/7303 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: newpatchset Gerrit-Change-Id: I9c0b823ccff6b0c37f5267c548d096c29b8caac3 Gerrit-PatchSet: 6 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Tim Armstrong <tarmstr...@cloudera.com> Gerrit-Reviewer: Dan Hecht <dhe...@cloudera.com> Gerrit-Reviewer: Matthew Jacobs <m...@cloudera.com> Gerrit-Reviewer: Tim Armstrong <tarmstr...@cloudera.com>