|
Root cause prediction based on bug reports |
|
Thomas Hirsch |
|
Institute of Software Technology |
|
Graz University of Technology |
|
Graz, Austria |
|
[email protected] Hofer |
|
Institute of Software Technology |
|
Graz University of Technology |
|
Graz, Austria |
|
[email protected] |
|
Abstract —This paper proposes a supervised machine learning |
|
approach for predicting the root cause of a given bug report. |
|
Knowing the root cause of a bug can help developers in the de- |
|
bugging process—either directly or indirectly by choosing proper |
|
tool support for the debugging task. We mined 54 755 closed |
|
bug reports from the issue trackers of 103 GitHub projects and |
|
applied a set of heuristics to create a benchmark consisting of |
|
10 459 reports. A subset was manually classified into three groups |
|
(semantic, memory, and concurrency) based on the bugs’ root |
|
causes. Since the types of root cause are not equally distributed, a |
|
combination of keyword search and random selection was applied. |
|
Our data set for the machine learning approach consists of 369 bug |
|
reports (122 concurrency, 121 memory, and 126 semantic bugs). |
|
The bug reports are used as input to a natural language processing |
|
algorithm. We evaluated the performance of several classifiers |
|
for predicting the root causes for the given bug reports. Linear |
|
Support Vector machines achieved the highest mean precision |
|
(0.74) and recall (0.72) scores. The created bug data set and |
|
classification are publicly available. |
|
Index Terms —bug report, bug benchmark, root cause prediction |
|
I. I NTRODUCTION |
|
Debugging is one of the most time-consuming parts in the |
|
software development process. While there exist numerous |
|
fault localization [1] and repair [2] techniques to support |
|
programmers in the debugging process, it is often unclear which |
|
techniques work best for a given bug. For this reason, Sobreira et |
|
al.[3] investigated the structure of Defects4J [4] bugs. For each |
|
bug, they determined the size of the patch, the repair action, |
|
and the change pattern. They have invited other researchers to |
|
investigate which types of bugs1can be handled by their repair |
|
tools. |
|
In this paper, we change the perspective of this research topic: |
|
instead of only providing root cause information for a bench- |
|
mark to help researchers in evaluating their tools, we predict |
|
the root cause for a given bug description so that programmers |
|
can choose a proper tool for their debugging problem. There |
|
are tools that focus on concurrency (e.g. ConcBugAssist [5]) |
|
or memory (e.g. Valgrind) bugs, while others are better suited |
|
for semantic bugs (e.g. Jaguar [6]). While some root causes |
|
can easily be determined when reading a bug report, other |
|
0©2020 IEEE. Personal use of this material is permitted. Permission from |
|
IEEE must be obtained for all other uses, in any current or future media, |
|
including reprinting/republishing this material for advertising or promotional |
|
purposes, creating new collective works, for resale or redistribution to servers |
|
or lists, or reuse of any copyrighted component of this work in other works. |
|
1http://program-repair.org/defects4j-dissection/root causes are not that obvious. Consider for example issue |
|
ticket #514 from TwelveMonkeys project2: |
|
TIFF: Invalid StripByteCounts when writing large resolution |
|
files (9800x8000) |
|
Hello, when writing a high resolution tiff file the stripByteCounts |
|
appears to be corrupt. An approx 300 mb output file has a single |
|
image strip with the byte count of: 4071696385 which is larger than |
|
the file itself. However when working with lower (more common) |
|
resolutions the meta for the image strips is created properly. [. . . ] |
|
This code creates the file with the incorrect meta data: |
|
// Input high resolution 48 bit depth final |
|
InputStream inStream = [. . . ] |
|
Attaching zipped image: 9800x8000 resolution 48bit depth.zip |
|
I’ve tested and reproduced the issue with the following versions: |
|
3.4.1, 3.4.2, 3.4.3 |
|
Thanks in advance, |
|
-Jesse |
|
Our goal is to provide information to the programmer about |
|
the root cause of this bug. For instance, the incorrect byte |
|
count mentioned in this bug report together with the information |
|
about high resolution can raise suspicion of an integer overflow |
|
occurring. |
|
We propose a supervised machine learning (ML) approach |
|
that uses the bug description from issue tickets to predict the |
|
root cause of the bug. For processing the text from the issue |
|
tickets, we make use of natural language processing (NLP). For |
|
creating the training set, we have mined bug reports from 103 |
|
GitHub projects and manually examined a subset, classifying |
|
them as memory, concurrency or semantic bugs based on the |
|
actual fix. Since the number of concurrency and memory bugs |
|
is usually very low [7], we have performed a keyword search in |
|
the commit messages of fixes to find more instances with these |
|
root causes. |
|
While the primary goal of this paper is the root cause |
|
prediction approach, the generated training data can be used |
|
as a benchmark for specific types of faults. Often, researchers |
|
focus on certain bug types when developing a fault localization |
|
or repair method. While these approaches have a high potential, |
|
their evaluation is often limited to a few real-world bugs or |
|
artificially seeded bugs, as mentioned in [8]. The training data |
|
set created in this paper can be used as a bug benchmark by |
|
researchers who are interested in certain types of bugs. It can |
|
be seen as a Java pendant to the C/C++ benchmark BugBench |
|
that also distinguishes memory, concurrency, and semantic bugs. |
|
Furthermore, it can be used to evaluate information retrieval |
|
based bug localization approaches [9]. |
|
2https://github.com/haraldk/TwelveMonkeys/issues/514 |
|
©2020 IEEE, DOI: 10.1109/ISSREW51248.2020.000671arXiv:2103.02372v1 [cs.SE] 3 Mar 2021The contributions of this work can be summarized as: |
|
a machine learning approach for predicting the root cause |
|
for a given bug report with a mean precision of 0.74 and |
|
a mean recall of 0.72, |
|
a data set consisting of 10 459 bug reports and fixes from |
|
103 GitHub repositories, |
|
a data set of 122 concurrency, 121 memory, and 269 |
|
semantic bugs with detailed sub-categories, and |
|
a framework for building such data sets. |
|
The created data sets, all scripts, and the categorization are |
|
publicly available.3The structure of this paper is as follows: |
|
Section II introduces the main root cause categories and their |
|
sub-categories. Section III explains how we have collected |
|
closed bug reports and their corresponding fixes. Section IV |
|
presents the machine learning approach. We discuss the results |
|
and threats to validity in Section V. Section VI discusses the |
|
related work and Section VII concludes the paper. |
|
II. C LASSIFICATION SCHEMA |
|
We use three main categories and 18 detailed root causes as |
|
described in Table I. The semantic and memory sub-categories |
|
are based on Tan et al. [7]; the concurrency sub-categories are |
|
based on Zhou et al. [10]. |
|
A problem with post mortem bug classification arises through |
|
often unclear separation of the actual fix from other code |
|
changes, e.g., commits that include more than one bug fix, |
|
commits that include the bug fix aside of some refactoring |
|
or new extension, or bug fixes that are scattered over multiple |
|
commits. Additionally, it is difficult to distinguish a workaround |
|
from a fix [11]. All of the above make it hard to correctly |
|
identify the fix and to properly categorize the root cause. To deal |
|
with these issues, we have added a confidence value ranging |
|
from 1-10 that reflects our confidence on the correctness of |
|
our classification: A confidence level of 10 indicates showcase |
|
quality; 9 indicates that we are very confident about the main |
|
category and the subcategory; 8 indicates that we are very |
|
confident about main category and subcategory assigned, but a |
|
different subcategory cannot be ruled out with 100 % certainty. |
|
For example, differentiating “processing” and “missing case” |
|
is often not possible without having the knowledge of the |
|
programmer who wrote the code. A confidence level of 7 or be- |
|
low indicates doubts about the chosen subcategory. Confidence |
|
levels between 3 and 5 indicate a strong confidence about the |
|
main category, but the subcategories were not identifiable. A |
|
confidence level of 2 indicates doubts about the main category |
|
while a level of 1 indicates that it was not possible to determine |
|
the main root cause category for the bug. |
|
III. D ATA ACQUISITION |
|
In this section, we provide details on the collection of the |
|
bug data set that builds the basis for creating the training set |
|
for the machine learning approach. |
|
Purpose of the data set. The data set should provide a realistic |
|
distribution of different bug types, and should serve as basis for |
|
3https://doi.org/10.5281/zenodo.3973048TABLE I |
|
ROOT CAUSE CATEGORIES AND SUB -CATEGORIES |
|
Semantic Description |
|
Exception handl. Missing or improper exception handling. |
|
Missing case Faults due to unawareness of a certain case or simply |
|
a forgotten implementation. |
|
Processing Incorrect implementation (e.g. miscalculations, in- |
|
correct method output, wrong method/library usage). |
|
Typo Ambiguous naming, typos in SQL calls/URLs/paths. |
|
Dependency The code can be built but behaves unexpected be- |
|
cause of changes in a foreign system (e.g. update of |
|
utilized library or underlying OS). |
|
Other All other semantic faults. |
|
Memory |
|
Buffer overflow Buffer overflows, not overflowing numeric types. |
|
Null pointer deref. All null pointer dereferences. |
|
Uninit. mem. read All uninitialized memory reads except null pointer |
|
dereference. |
|
Memory leak Memory leak. |
|
Dangling pointer Dangling pointer. |
|
Double free Double free. |
|
Other All other memory bugs. |
|
Concurrency |
|
Order violation Missing or incorrect synchronization, e.g. object is |
|
dereferenced by thread B before it is initialized by |
|
thread A. |
|
Race condition Two or more threads access the same resource with |
|
at least one being a write access and the access is |
|
not ordered properly. |
|
Atomic violation Constraints on the interleaving of operations are |
|
missing. This happens when atomicity of a certain |
|
code region was assumed but failed to guarantee |
|
atomicity in the implementation. |
|
Deadlock Two or more threads wait for the other one to release |
|
a resource. |
|
Other All other concurrency bugs. |
|
experiments with various fault localization and ML experiments. |
|
The bugs should be real world Java bugs. |
|
Project selection. We chose 103 GitHub Java projects to |
|
source our data set. Primary selection criteria were a well known |
|
organization driving the project, or the project having a high |
|
star rating on GitHub. However, the list also contains lesser |
|
known projects that were already used in other research [4], |
|
[12], [13]. The selection process was performed manually. All of |
|
the projects utilize GitHub’s built-in issue tracker together with |
|
its labeling system, and have at least 100 closed issues identified |
|
as bugs. The project sizes range from 13k Java LOC (Lines Of |
|
Code) for HikariCP4to 1.7M Java LOC for Elasticsearch5. The |
|
full list of mined projects can be found in the online appendix3. |
|
Bug ticket identification. We identified bugs via the labels |
|
used in the issue tickets and we only considered closed issue |
|
tickets. In order to omit feature requests, maintenance tickets |
|
and other non-bug issues, we only considered issues whose |
|
labels contain “bug”, “defect”, or “regression”. |
|
Filtering criteria. GitHub automatically links commits to |
|
issue tickets based on issue ids and provides this data together |
|
with issue tickets. We only consider issues for which at least |
|
4https://github.com/brettwooldridge/HikariCP |
|
5https://github.com/elastic/elasticsearch |
|
©2020 IEEE, DOI: 10.1109/ISSREW51248.2020.000672one commit is linked to the issue, and all linked commits are |
|
still available in the Git repository. If any of the commits are |
|
linked to multiple issues, or the commit message suggests that |
|
the fix is done aside of other changes, the issue is discarded. As |
|
of writing this, we omit issues whose commits do not contain |
|
changes in production Java code. We plan to lift this limitation |
|
to incorporate other root causes, e.g. in the documentation or |
|
build system in the future. |
|
We use Gumtree Spoon AST Diff6[14] to create Java |
|
aware diffs. To manage overwhelming runtime and memory |
|
requirements arising from the size of the data set, we limit the |
|
size and number of the commits per issue. We only consider |
|
issues where the number of commits linked to the issue is |
|
smaller than 10, the number of files changed per commit is |
|
smaller than 20, and the number of lines changed per commit |
|
is smaller than 250. Our analysis shows that these limitations |
|
only remove less than 3 % of the issues. |
|
The data set. In total, 54 755 issues have been mined from |
|
GitHub. Following the filtering criteria described above leaves |
|
us with 10 459 issues that form the basis for our further |
|
investigations. This bug data set consists of: |
|
textual bug report including metadata in form of time- |
|
stamps and user names, |
|
all commits associated to each bug report including meta- |
|
data as commit message and git stats, and |
|
Java aware diff statistics and location of the changes in |
|
terms of file, class, and method. |
|
IV. M ACHINE LEARNING APPROACH |
|
We employ an NLP approach, vectorizing the textual bug |
|
reports into unigrams and bigrams, to train a model for auto- |
|
mated classification along our fault classification schema. This |
|
approach calculates a frequency vector from words and word |
|
pairs occurring in the input text that is used as feature vector |
|
for the classifier. |
|
Input preprocessing. To increase performance of the classifier, |
|
we applied the following preprocessing steps: |
|
Stop word removal (i.e. removing common words that are |
|
not adding any value) |
|
Case folding (i.e. converting all characters to lower case) |
|
Stemming (i.e. reducing each word to its word stem) |
|
The bug reports often include stack traces, exceptions, and log |
|
outputs. Currently, we process them in the same way as the |
|
rest of the input text. In future work, we will investigate the |
|
usefulness of domain specific preprocessing of these artifacts. |
|
Training set creation. Figure 1 provides an overview of the |
|
training set creation. We manually classified 160 randomly |
|
selected issues and identified 119 semantic, 2 memory, and 4 |
|
concurrency bugs. 35 issues were not classified because the bug |
|
reports were non-English, feature requests, deemed not a bug, or |
|
issues for which we were not confident about the sub-category |
|
(confidence level <8). |
|
Concurrency and memory bugs are usually rare, accounting |
|
for 2 % respectively 6 % of all bugs [7], [15], [16], which poses |
|
6https://github.com/SpoonLabs/gumtree-spoon-ast-diff |
|
Random sample of 471 issuesFilter criteria: |
|
•Commits linked |
|
•Commits only address |
|
one issue |
|
•Change of production |
|
Java code |
|
•Reasonable size for fix |
|
11954 755 issues labeled as bug |
|
from 103 GitHub projects |
|
10 459 complete issues |
|
Random |
|
sample |
|
of 160 |
|
issues756 potential memory or |
|
concurrency bugsRandom |
|
selectionKeyword |
|
search |
|
150 semantic |
|
bugs |
|
keyword |
|
biased121 |
|
memory |
|
bugs122 |
|
concurrency |
|
bugs118 |
|
2 4150 119 |
|
Filter criteria: |
|
•Classification |
|
confidence > 7 |
|
•English issue text |
|
•Bug, not hidden |
|
feature request |
|
119 |
|
semantic |
|
Bugs |
|
369 issues for machine learning approachAll All All5 % |
|
(7)Random |
|
selection |
|
119Fig. 1. Training set creation |
|
a challenge for the creation of reasonably sized training sets. |
|
For this reason, we have performed a keyword search on the |
|
commit messages linked to the issues to identify candidates of |
|
memory and concurrency bugs analog to Ray et al. ’s approach |
|
[15], resulting in a total of 756 issues. As of writing this, 471 |
|
randomly selected issues from this set have been examined and |
|
classified. 150 semantic, 119 memory, and 118 concurrency |
|
bugs have been identified in this sample. 84 issues could not be |
|
classified due to the reasons mentioned above. |
|
Training set composition. To avoid a bias towards the se- |
|
mantic bugs that were “accidentally found” during the manual |
|
classification of the keyword search results and to have approx- |
|
imately equally large training sets, we reduced their volume |
|
to 5 % of all semantic bugs. This is a rather high estimate |
|
given the fact, that only 7.2 % of all bugs have been reported |
|
in the keyword search and only one third of these bugs are |
|
actually semantic bugs. Further, using separate data bases for |
|
the keyword search (commit messages) and training set for our |
|
ML classifier (bug reports) makes us confident that the bias |
|
introduced by the keywords is limited. As of writing this, our |
|
training set consists of 122 concurrency bugs, 121 memory |
|
bugs, and 126 semantic bugs. The complete training set consists |
|
of 369 textual bug reports. |
|
Classifiers. We applied various supervised ML classifier |
|
algorithms on our data set, namely Multinomial Naive Bayes |
|
(MNB), Linear Support Vector (LSVC), Linear Support Vector |
|
with Stochastic Gradient Descent learning (SGDC), Random |
|
Forrest (RFC), and Logistic Regression (LRC). The selection |
|
of classifiers is based on their suitability for multi-class clas- |
|
sification problems based textual inputs, and their application |
|
in similar research. Support vector machines have been used in |
|
©2020 IEEE, DOI: 10.1109/ISSREW51248.2020.000673comparable endeavors [7], [15]–[18]; the same applies to naive |
|
Bayes [7], [16], [17], [19]–[21], logistic regression [20], [21], |
|
and decision tree based algorithms [7], [20], [21]. |
|
Experiment. The 369 bug reports were split into a training |
|
set (80 %) and a test set (20 %). We performed 5-fold cross |
|
validation on the training set for each classifier, using grid |
|
search for hyperparameter tuning. Mean accuracy was used as |
|
scoring metric in the grid search. The highest scoring model for |
|
each classifier was then evaluated on the test set yielding the |
|
final score for this classifier. This experiment was performed |
|
10 times, followed by manual examination of its results and |
|
corresponding hyperparameters to reduce the grid search space. |
|
Finally, to enable comparison of the classifiers given the small |
|
input data set, the above described experiment with the reduced |
|
hyperparameter set was performed 100 times with randomized |
|
test and training splits. The employed set of hyperparameters, |
|
and grid search results for each experiment, can be found in the |
|
online appendix. |
|
V. R ESULTS |
|
A. Classification results |
|
We graphically compare the classifiers’ performance by |
|
means of the weighted averages of F1, precision, and recall |
|
in Figure 2 and we report mean, median, standard deviation, |
|
min, and max of each classifier in Table II based on the scores |
|
of 100 runs. Please note that the F1 scores are computed for |
|
the individual test runs and then the mean, median, standard |
|
deviation, min, and max values of these F1 scores are computed. |
|
Thus, they cannot be computed from the precision and recall |
|
given in the table. |
|
We observed a tight clustering of classifiers, which is also |
|
evident in individual runs, although individual runs exhibit |
|
varying performances. We attribute this behavior to the small |
|
data set size and high variance in data quality. The best overall |
|
performance was achieved with LSVC, with mean F1 (0.72), |
|
precision (0.74), and recall (0.72). LSVC also produced the |
|
highest observed scores in an individual run, yielding F1 (0.85), |
|
precision (0.88), and recall (0.85). |
|
B. Discussion |
|
The biggest challenge lies in the creation of a reasonably |
|
sized data set. Further, varying data quality constitutes a sig- |
|
nificant problem. The textual bug reports in our data set range |
|
from only 5 words to 60kB of text per report. However, our |
|
examination of those bug tickets shows that the length is not |
|
necessarily correlating with the quality in terms of usefulness |
|
for the developer. Issue #4960 from Elasticsearch7is an example |
|
of a bug report that requires context and knowledge about the |
|
project for understanding: |
|
Filtered query parses name incorrectly |
|
There are bug reports that merely describe the impact, e.g. |
|
issue #338 from the Redisson project8: |
|
7https://github.com/elastic/elasticsearch/issues/4960 |
|
8https://github.com/redisson/redisson/issues/338 |
|
Fig. 2. Mean weighted average precision, recall and F1 score |
|
TABLE II |
|
WEIGHTED AVERAGE PRECISION ,RECALL ,AND F1SCORES (100 RUNS ) |
|
Classifier Precision Recall F1 |
|
MeanLRC 0.73 0.71 0.71 |
|
RFC 0.72 0.62 0.62 |
|
SGDC 0.74 0.71 0.71 |
|
LSVC 0.74 0.72 0.72 |
|
MNB 0.72 0.70 0.70 |
|
MedianLRC 0.73 0.70 0.70 |
|
RFC 0.72 0.62 0.62 |
|
SGDC 0.74 0.70 0.71 |
|
LSVC 0.74 0.72 0.72 |
|
MNB 0.73 0.70 0.70 |
|
Std. dev.LRC 0.046 0.048 0.048 |
|
RFC 0.053 0.076 0.082 |
|
SGDC 0.045 0.049 0.049 |
|
LSVC 0.046 0.046 0.046 |
|
MNB 0.045 0.049 0.049 |
|
MinLRC 0.63 0.62 0.62 |
|
RFC 0.53 0.39 0.38 |
|
SGDC 0.64 0.62 0.63 |
|
LSVC 0.65 0.64 0.63 |
|
MNB 0.60 0.57 0.57 |
|
MaxLRC 0.84 0.82 0.82 |
|
RFC 0.85 0.77 0.77 |
|
SGDC 0.86 0.84 0.84 |
|
LSVC 0.88 0.85 0.85 |
|
MNB 0.83 0.82 0.82 |
|
©2020 IEEE, DOI: 10.1109/ISSREW51248.2020.000674New version 2.1.4 or greater performance is low. |
|
When I use redisson 2.1.3 the ubuntu’s load average is 1.8 2.3; but |
|
I use 2.1.4 or greater, the load average is often greater than 3.00, |
|
my java application often overload. |
|
In some cases, the bug reports point right away at the fault, |
|
e.g. Netty issue #18789: |
|
WebSocket08FrameDecoder leaks ByteBuf when payload is |
|
masked |
|
Further research is required to determine metrics to mea- |
|
sure bug report quality for our purpose. On the other end of |
|
the spectrum, for very long bug reports, additional text pre- |
|
processing is required. Heuristics for reduction or removal of |
|
artifacts have to be implemented. Such artifacts are stack traces, |
|
code snippets, log outputs, or similar text portions, whose size |
|
is disproportionate to the added information. |
|
C. Threats to validity |
|
The selection of bugs from the issue tickets by searching for |
|
certain labels is a threat to the internal validity. While we have |
|
considered a wide range of bug labels, we cannot rule out to |
|
miss bugs with special labels or wrongly labeled bugs. A study |
|
on 7000 issue reports from five open-source projects showed |
|
that up to 40 % of the issues were wrongly labeled [22]. |
|
Manually categorizing the root cause might be error-prone |
|
and the true root cause of the bug can only be determined |
|
by the original programmer. For this reason, we indicated the |
|
confidence level for each bug we categorized and excluded bugs |
|
with a low confidence level. Furthermore, the fix might be a |
|
workaround instead of a fix of the true fault. |
|
The keyword search might only reveal certain types of |
|
memory and concurrency bugs. We have tried to avoid a bias in |
|
the classification towards the words used in the keyword search |
|
by performing the keyword search on the commit messages and |
|
NLP for classification on the bug description. |
|
The small sample size is the biggest threat to external validity. |
|
In future work, we will therefore enlarge the training set. The |
|
performance of this approach may vary based on the software |
|
domain of the examined project. We tried to counteract this |
|
by including software projects to source our data set. However, |
|
data mining was exclusively performed on open source projects. |
|
Further, most of the examined projects are libraries. In contrast |
|
to end-user software, bug reports for libraries are almost ex- |
|
clusively written by other developers. Such bug reports often |
|
already contain insights into the underlying problem. Further, |
|
our approach may not work as good for bug descriptions of |
|
software written in a different programming language. |
|
VI. R ELATED WORK |
|
Ray et al. [15] analyzed more 560 000 bug fixes from |
|
729 GitHub projects written in 17 languages. They classified |
|
the root causes and impacts for 10 % of the bugs by searching |
|
for keywords in the commit messages and trained a supervised |
|
ML approach to classify the remaining 90 % of the bugs. They |
|
9https://github.com/netty/netty/issues/1878validated their approach by manual classifying 180 bug fixes |
|
(83.7 % precision, 84.3 % recall). While we also rely on a |
|
keyword search, we did not perform the keyword search on |
|
the same text that was used in NLP to avoid biasing. |
|
Li and colleagues [16] classified the root cause, impact, |
|
and software component of nearly 30 000 Bugzilla entries |
|
using NLP with SVM, Winnow, Perceptron and Naive Bayes |
|
as classifiers. Their training set consists of 709 bugs (51 % |
|
randomly sampled, 36 % security-related, and 13 % concurrency |
|
bugs). |
|
Tan et al. [7] manually classified 339 bugs from randomly |
|
selected fixed issues of three open-source projects into the |
|
dimensions root cause, impact, and component. Because of |
|
the low number of concurrency bugs in the sample, they |
|
performed a keyword search to identify additional concurrency |
|
bugs. Semantic bugs are the dominant root cause with 70- |
|
87 %. The Linux kernel has nearly 13.6 % concurrency bugs; |
|
the other projects (Mozilla and Apache) have a lower number |
|
of concurrency bugs with 1.2 % and 5.2 %. Furthermore, the |
|
authors automatically classified more than 100 000 bugs using |
|
a supervised ML (precision: 67 % for memory and 93 % for |
|
semantic bugs, recall: 57 % resp. 95 %). |
|
Ortu et al. [17] investigated whether there are differences |
|
in the characteristics of high and low priority defects in more |
|
than 1200 open-source software projects. Therefore, they trained |
|
different supervised machine learning classifiers to predict the |
|
root cause, impact, and software component. |
|
Thung et al. [18] used machine learning to classify bugs ac- |
|
cording to the Orthogonal Defect Classification (ODC) scheme. |
|
They distinguished three defect groups: data and control flow, |
|
structural, and non-functional. They manually classified 500 |
|
bugs that serve as training set. They use the description of the |
|
bug as well as the fixes to train a model. The SVM multi- |
|
class classification algorithm performed best (69 % precision, |
|
70 % recall). Lopes and colleagues [23] applied different ML |
|
algorithms on bug descriptions to classify bugs according to |
|
different ODC dimensions. They manually categorized more |
|
than 4000 fixed bugs from three NoSQL databases. Recurrent |
|
Neural Networks have the highest accuracy when predicting |
|
the activity (47.6 %) and impact (33.3 %). Linear support vector |
|
machines are suited best to predict the target (accuracy 85.5 %) |
|
and the defect type (34.7 %). |
|
Hern ´andez-Gonz ´alez and colleagues [19] proposed a learning |
|
from crowds ML approach. The training data consists of bug |
|
reports and labels for OCD’s impact dimension. Each bug report |
|
was labeled by five annotators. In the majority of the cases, the |
|
annotators disagree on the labels. In the learning from crowds |
|
paradigm, the individual labels are taken in the machine learning |
|
training instead of the label that was assigned by the majority |
|
of the annotators. |
|
Antoniol et al. [20] use decision trees, naive Bayes and |
|
logistic regression to classify issue reports as bug or feature |
|
request. Their approach was able to correctly classify 77-82 % |
|
of the issues. Chawla and Singh [21] also classify issue reports |
|
as bug or other request. They receive an accuracy of 84-91 %. |
|
©2020 IEEE, DOI: 10.1109/ISSREW51248.2020.000675VII. C ONCLUSION AND FUTURE WORK |
|
The presented approach automatically predicts the root cause |
|
for a given bug report. This information can be used by the |
|
developer to choose a proper debugging tool. It can also be |
|
used by a meta-debugging approach to recommend a debugging |
|
tool. The data set created in this work can be used to evaluate |
|
which debugging tools are particularly well-suited to support |
|
programmers in the debugging process of a particular bug |
|
instance. In addition, the proposed approach can be utilized |
|
for building benchmarks of specific bug types. This benchmark |
|
is especially suitable for evaluating IR-based fault localization |
|
techniques since it includes textual data in form of bug reports |
|
and commit messages, as well as detailed information on the |
|
fix location. |
|
During the manual classification, we have noticed recurring |
|
fault patterns. We will investigate if we can establish links be- |
|
tween these fault patterns and code-smells detected by existing |
|
code analysis tools such as SonarQube10. If so, knowledge about |
|
the bug type combined with reports from code analysis tools can |
|
be utilized to aid fault localization. |
|
Besides that, we will improve the approach by pre-processing |
|
stack trace information and other artifacts (if available in the bug |
|
report). Currently, stack trace information is treated the same |
|
way as human written text. |
|
Since a detailed predicted root cause is even more helpful, |
|
we will refine the prediction to the sub-categories. To do so, we |
|
have to enlarge the training set. Since certain subcategories will |
|
be underrepresented in the training set, we will up-sample those |
|
categories by means of the Synthetic Minority Over-sampling |
|
TEchnique (SMOTE) [24]. |
|
ACKNOWLEDGMENT |
|
The work described in this paper has been funded by the |
|
Austrian Science Fund (FWF): P 32653 (Automated Debugging |
|
in Use). |
|
REFERENCES |
|
[1] W. E. Wong, R. Gao, Y . Li, R. Abreu, and F. Wotawa, “A Survey on |
|
Software Fault Localization,” IEEE Transactions on Software Engineering , |
|
vol. 42, no. 8, pp. 707–740, aug 2016. |
|
[2] L. Gazzola, D. Micucci, and L. Mariani, “Automatic Software Repair: A |
|
Survey,” IEEE Transactions on Software Engineering , vol. 45, no. 1, pp. |
|
34–67, jan 2019. |
|
[3] V . Sobreira, T. Durieux, F. Madeiral, M. Monperrus, and M. A. Maia, |
|
“Dissection of a Bug Dataset: Anatomy of 395 Patches from Defects4J,” |
|
25th IEEE International Conference on Software Analysis, Evolution and |
|
Reengineering (SANER 2018) , vol. 2018-March, pp. 130–140, jan 2018. |
|
[Online]. Available: http://dx.doi.org/10.1109/SANER.2018.8330203 |
|
[4] R. Just, D. Jalali, and M. D. Ernst, “Defects4J: a database of |
|
existing faults to enable controlled testing studies for Java programs,” |
|
inInternational Symposium on Software Testing and Analysis (ISSTA |
|
2014) . ACM Press, jul 2014, pp. 437–440. [Online]. Available: |
|
http://dl.acm.org/citation.cfm?doid=2610384.2628055 |
|
[5] S. Khoshnood, M. Kusano, and C. Wang, “ConcBugAssist: Constraint |
|
solving for diagnosis and repair of concurrency bugs,” in Int. Symp. on |
|
Software Testing and Analysis (ISSTA 2015) . ACM, 2015, pp. 165–176. |
|
[6] H. L. Ribeiro, H. A. De Souza, R. P. A. De Araujo, M. L. Chaim, and |
|
F. Kon, “Jaguar: A Spectrum-Based Fault Localization Tool for Real- |
|
World Software,” in 11th International Conference on Software Testing, |
|
Verification and Validation (ICST 2018) . IEEE, may 2018, pp. 404–409. |
|
10https://www.sonarqube.org/[7] L. Tan, C. Liu, Z. Li, X. Wang, Y . Zhou, and C. Zhai, “Bug characteristics |
|
in open source software,” Empirical Software Engineering , vol. 19, no. 6, |
|
pp. 1665–1705, oct 2014. |
|
[8] Y . Tang, Q. Gao, and F. Qin, “LeakSurvivor: Towards Safely Tolerating |
|
Memory Leaks for Garbage-Collected Languages,” in USENIX Annual |
|
Technical conference , 2008, pp. 307–320. |
|
[9] T. D. B. Le, F. Thung, and D. Lo, “Will this localization tool be effective |
|
for this bug? Mitigating the impact of unreliability of information retrieval |
|
based bug localization tools,” Empirical Software Engineering , vol. 22, |
|
no. 4, pp. 2237–2279, aug 2017. |
|
[10] B. Zhou, I. Neamtiu, and R. Gupta, “Predicting concurrency bugs: |
|
How many, what kind and where are they?” in 9th International |
|
Conference on Evaluation and Assessment in Software Engineering |
|
(EASE’15) . ACM, apr 2015, pp. 1–10. [Online]. Available: https: |
|
//doi.org/10.1145/2745802.2745807 |
|
[11] M. B ¨ohme, E. O. Soremekun, S. Chattopadhyay, E. Ugherughe, and |
|
A. Zeller, “Where is the bug and how is it fixed? An experiment |
|
with practitioners,” in 11th Joint Meeting on Foundations of Software |
|
Engineering (ESEC/FSE 2017) , vol. Part F1301. Association for |
|
Computing Machinery, aug 2017, pp. 117–128. [Online]. Available: |
|
http://dl.acm.org/citation.cfm?doid=3106237.3106255 |
|
[12] P. Gyimesi, G. Gyimesi, Z. T ´oth, and R. Ferenc, “Characterization of |
|
source code defects by data mining conducted on GitHub,” in Lecture |
|
Notes in Computer Science , vol. 9159. Springer, 2015, pp. 47–62. |
|
[13] Z. T ´oth, P. Gyimesi, and R. Ferenc, “A public bug database of GitHub |
|
projects and its application in bug prediction,” in 16th Int. Conference |
|
on Computational Science and Its Applications (ICCSA’16) , vol. 9789. |
|
Lecture Notes in Computer Science, Springer, 2016, pp. 625–638. |
|
[14] J. R. Falleri, F. Morandat, X. Blanc, M. Martinez, and M. Monperrus, |
|
“Fine-grained and accurate source code differencing,” in 29th ACM/IEEE |
|
International Conference on Automated Software Engineering (ASE |
|
2014) . ACM, 2014, pp. 313–323. [Online]. Available: http://dl.acm.org/ |
|
citation.cfm?doid=2642937.2642982 |
|
[15] B. Ray, D. Posnett, V . Filkov, and P. Devanbu, “A large scale study |
|
of programming languages and code quality in GitHub,” in ACM |
|
SIGSOFT Symposium on the Foundations of Software Engineering |
|
(FSE’14) . ACM, nov 2014, pp. 155–165. [Online]. Available: |
|
http://dl.acm.org/citation.cfm?doid=2635868.2635922 |
|
[16] Z. Li, L. Tan, X. Wang, S. Lu, Y . Zhou, and C. Zhai, “Have things |
|
changed now?: An empirical study of bug characteristics in modern open |
|
source software,” in 1st Workshop on Architectural and System Support |
|
for Improving Software Dependability (ASID’06) , 2006, pp. 25–33. |
|
[17] M. Ortu, G. Destefanis, S. Swift, and M. Marchesi, “Measuring high and |
|
low priority defects on traditional and mobile open source software,” |
|
in7th International Workshop on Emerging Trends in Software Metrics |
|
(WETSoM 2016) . ACM, may 2016, pp. 1–7. [Online]. Available: |
|
http://dl.acm.org/citation.cfm?doid=2897695.2897696 |
|
[18] F. Thung, D. Lo, and L. Jiang, “Automatic defect categorization,” in |
|
Working Conf. on Reverse Engineering (WCRE) , 2012, pp. 205–214. |
|
[19] J. Hern ´andez-Gonz ´alez, D. Rodriguez, I. Inza, R. Harrison, and J. A. |
|
Lozano, “Learning to classify software defects from crowds: A novel |
|
approach,” Applied Soft Computing Journal , vol. 62, pp. 579–591, 2018. |
|
[20] G. Antoniol, K. Ayari, M. Di Penta, F. Khomh, and Y .-G. Gu ´eh´eneuc, |
|
“Is it a bug or an enhancement?” in Conference of the center |
|
for advanced studies on collaborative research meeting of minds |
|
(CASCON ’08) . ACM Press, 2008, pp. 304—-318. [Online]. Available: |
|
http://portal.acm.org/citation.cfm?doid=1463788.1463819 |
|
[21] I. Chawla and S. K. Singh, “An automated approach for bug |
|
categorization using fuzzy logic,” in 8th India Software Engineering |
|
Conference (ISEC) . ACM, feb 2015, pp. 90–99. [Online]. Available: |
|
http://dl.acm.org/citation.cfm?doid=2723742.2723751 |
|
[22] K. Herzig, S. Just, and A. Zeller, “It’s not a bug, it’s a feature: How |
|
misclassification impacts bug prediction,” in International Conference on |
|
Software Engineering (ICSE 2013) , 2013, pp. 392–401. |
|
[23] F. Lopes, J. Agnelo, C. A. Teixeira, N. Laranjeiro, and J. Bernardino, |
|
“Automating orthogonal defect classification using machine learning al- |
|
gorithms,” Future Generation Computer Systems , vol. 102, pp. 932–947, |
|
jan 2020. |
|
[24] N. V . Chawla, K. W. Bowyer, L. O. Hall, and W. P. Kegelmeyer, |
|
“SMOTE: Synthetic minority over-sampling technique,” Journal of |
|
Artificial Intelligence Research , vol. 16, pp. 321–357, jan 2002. [Online]. |
|
Available: https://www.jair.org/index.php/jair/article/view/10302 |
|
©2020 IEEE, DOI: 10.1109/ISSREW51248.2020.000676 |