Joe McDonnell has submitted this change and it was merged. ( http://gerrit.cloudera.org:8080/19865 )
Change subject: IMPALA-12122: use isb instead of yield on arm64 ...................................................................... IMPALA-12122: use isb instead of yield on arm64 A "yield" instruction in aarch64 is essentially a nop, and does not cause enough delay to help backoff. "isb" is a barrier that, especially inside a loop, creates a small delay without consuming ALU resources. Experiments show that adding the isb instruction improves stability and reduces result jitter. Adding more delay than a single isb reduces performance. Change-Id: If14eaa8a4b445034d81bf68037e702e6d16b1181 Reviewed-on: http://gerrit.cloudera.org:8080/19865 Reviewed-by: Joe McDonnell <[email protected]> Tested-by: Impala Public Jenkins <[email protected]> --- M be/src/gutil/yield_processor.h 1 file changed, 6 insertions(+), 1 deletion(-) Approvals: Joe McDonnell: Looks good to me, approved Impala Public Jenkins: Verified -- To view, visit http://gerrit.cloudera.org:8080/19865 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: merged Gerrit-Change-Id: If14eaa8a4b445034d81bf68037e702e6d16b1181 Gerrit-Change-Number: 19865 Gerrit-PatchSet: 4 Gerrit-Owner: Anonymous Coward <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Joe McDonnell <[email protected]>
