tree 216320f8e7430c8151a010dec819a5741d201bdd
parent a22ca7bf8b69ee3a747947be42d2895f82ffae48
author luochen01 <cluo8@uci.edu> 1509120859 -0700
committer Luo Chen <cluo8@uci.edu> 1509509485 -0700

[ASTERIXDB-2133] Fix unncessary binary search in GroupFrameAccessor

- user model changes: no
- storage format changes: no
- interface changes: no

Details:
- GroupFrameAccessor holds a list of frames from a run during the merge
step of merge sort. However, everytime we access a tuple, it performs
binary search to get the physical tuple index. This patch fixes this
by remembering the last accessed frame. It is expected that tuples
are accessed sequentially (since it's the merge step), which greatly
reduces binary searches

Change-Id: I4a1b19ad47f6b1dda4bd5c417932e4c9ba36a714
Reviewed-on: https://asterix-gerrit.ics.uci.edu/2079
Sonar-Qube: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Contrib: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Ian Maxon <imaxon@apache.org>