Dan Hecht has posted comments on this change.

Change subject: Use AVX2 operations to speedup Bloom filters by 10-100%.
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Patch Set 7:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/3338/7/be/src/util/bloom-filter.h
File be/src/util/bloom-filter.h:

Line 176:   if (CpuInfo::IsSupported(CpuInfo::AVX2)) {
> So TESTL is cheaper than cmp eax, 1?
"const" doesn't make something a compile time constant. It just means that once 
initialized, it won't change (unless const is cast away).  Maybe you are 
thinking of "static const"., but this field is not a compile time constant. It 
depends on what CPU we're running on which is only known at runtime.  It is a 
code-gen time constant, however, which is why I said it can later be optimized 
via code-gen.


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Gerrit-MessageType: comment
Gerrit-Change-Id: I6fef4f6652876f8fd7e3f0e41431702380418c98
Gerrit-PatchSet: 7
Gerrit-Project: Impala
Gerrit-Branch: cdh5-trunk
Gerrit-Owner: Jim Apple <[email protected]>
Gerrit-Reviewer: Dan Hecht <[email protected]>
Gerrit-Reviewer: Jim Apple <[email protected]>
Gerrit-Reviewer: Mostafa Mokhtar <[email protected]>
Gerrit-Reviewer: Tim Armstrong <[email protected]>
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