Tim Armstrong has posted comments on this change.

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


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)) {
> I am interested in closing up this debate.
I think it's unlikely to make a measurable difference reading a word from a 
fixed address in the data segment and applying  a bitmask versus reading a byte 
at a fixed offset from the bloom filter pointer.

My preference is to keep it as-is so I don't have to revert the change in the 
codegen patch, but either is fine to get the patch committed.


-- 
To view, visit http://gerrit.cloudera.org:8080/3338
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

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]>
Gerrit-HasComments: Yes

Reply via email to