Tim Armstrong has posted comments on this change. Change subject: IMPALA-3286: Software prefetching for hash table build. ......................................................................
Patch Set 8: (1 comment) http://gerrit.cloudera.org:8080/#/c/2896/8/be/src/exec/hash-table.inline.h File be/src/exec/hash-table.inline.h: Line 131: 1 > I think the prefetch level maps to instructions prefetch{0-2} and prefetchn This might change if we used a smaller batch size - the benefits of getting it into LLC is presumably bigger if there's no/minimal chance of it getting evicted before its needed. Anyway, we should just consider rerunning that experiment to see if the result changes if/when we reduce the batch size. -- To view, visit http://gerrit.cloudera.org:8080/2896 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: Ib85e7fc162ad25c849b9e716b629e226697cd940 Gerrit-PatchSet: 8 Gerrit-Project: Impala Gerrit-Branch: cdh5-trunk Gerrit-Owner: Michael Ho <[email protected]> Gerrit-Reviewer: Dan Hecht <[email protected]> Gerrit-Reviewer: Marcel Kornacker <[email protected]> Gerrit-Reviewer: Michael Ho <[email protected]> Gerrit-Reviewer: Mostafa Mokhtar <[email protected]> Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-HasComments: Yes
