Diptikalyan Saha is a Stony Brook alum (PhD, 2006) who is currently a
research staff member at IBM Research Labs in Bangalore, India.
(http://researcher.watson.ibm.com/researcher/view.php?person=in-diptsaha)
He will be visiting Stony Brook on July 2, and will give a talk at 2pm
in Room 120 of the new CS building.
Title: Fault Localization in Data-centric Programs and Partitioned Path
Problems
Abstract:
In this talk I will present our experience of developing an automated
technique for fault localization in data-centric programs. Data-centric
programs primarily interact with databases to get collections of
content, process each entry in the collection(s), and output another
collection or write it back to the database. One or more entries in the
output may be faulty. In our approach, we gather the execution trace of
a faulty program. We use a novel, precise slicing algorithm to break the
trace into multiple slices, such that each slice maps to an entry in the
output collection. We then compute the semantic difference between the
slices that correspond to correct entries and those that correspond to
incorrect ones. The diff helps to identify potentially faulty
statements. We apply this technique for localizing faults in SAP-ABAP
programs. It turns out that getting execution trace efficiently for
SAP-ABAP programs is very challenging. So in the second part of the this
talk, I will present a novel trace collection framework, wherein, a
program is executed multiple times with the same input for different
sets of witnesses. The partial traces such obtained are then merged to
create the whole program trace. Such divide-and-conquer strategy enables
parallel collection of partial traces, thereby reducing the total time
of collection. The problem is particularly challenging as arbitrary
distribution of witnesses cannot guarantee correct formation of traces.
We provide and prove a necessary and sufficient condition for
distributing the witnesses which ensures correct formation of trace.
Moreover, we describe witness distribution strategies
