Dan Hecht has posted comments on this change.

Change subject: Impala-3286: Prefetching For Phj Probing.
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Patch Set 3:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/2959/3/be/src/exec/partitioned-hash-join-node.cc
File be/src/exec/partitioned-hash-join-node.cc:

Line 653:   BufferedTupleStream* build_rows[PARTITION_FANOUT];
> For slightly tighter cache footprint. The partition objects are probably la
what do you mean the are large enough to fit in a single cache line?
did you measure this helping performance? seems like it should be minimal given 
that there are only 16 of them so they should be hot pretty quickly...


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Gerrit-MessageType: comment
Gerrit-Change-Id: Ib42b93d99d09c833571e39d20d58c11ef73f3cc0
Gerrit-PatchSet: 3
Gerrit-Project: Impala
Gerrit-Branch: cdh5-trunk
Gerrit-Owner: Michael Ho <[email protected]>
Gerrit-Reviewer: Dan Hecht <[email protected]>
Gerrit-Reviewer: Michael Ho <[email protected]>
Gerrit-Reviewer: Mostafa Mokhtar <[email protected]>
Gerrit-Reviewer: Tim Armstrong <[email protected]>
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