In this paper we identify causes about why developers don't get desired performance from written Julia programs with Stack Overflow posts.

1. Synthesizing Program Execution
Time Discrepancies in Julia
Used for Scientific Software
Effat Farhana Nasif Imtiaz Akond Rahman

2. Scientific Software
2

3. Scientific Software in Julia
• Julia: Designed for scientific and numeric computing
o Scripting : syntax as Python
o Compiled : speed as C

4. Program Execution Time Discrepancies in Julia

5. Motivation
“Discrepancies in program execution time is a risk for scientific
software development, which should be mitigated by stakeholders”

6. Methodology
Filtering Qualitative
rating
Categories
Causes
SOTorrent Dataset
(Baltes et al.)

7. Category: Data structure

8. Category: Data analytics

9. Category: Language Transfer

10. Category: Language Utilities

11. Category: Parallel Programming

12. Category: Data Type

13. Category: Memory Allocation

14. Category: Filesystem Operation

15. Category: Scope Concern
Global
Local

16. Category Frequency
Category Q AQ VQ
Data Structure Concern (103) 0.36 1.68 556.38
Mathematics/Statistics/Machine Learning (57) 0.20 1.48 384.43
Language Transfer (42) 0.15 1.86 1678.12
Function/Package/Compilation (36) 0.13 1.39 581.50
Parallel Programming (34) 0.12 1.41 580.09
Data Type Concern (21) 0.07 1.52 239.00
Memory Allocation (16) 0.06 1.69 237.56
File Operation (12) 0.04 1.25 454.67
Scope Concern (7) 0.02 1.57 288.71

17. Cause: Inefficient Program Construct

18. Cause: Knowledge Gap
Memory Management Julia Knowledge Parallel Programming

19. Cause: Knowledge Gap
Macro Data Structure Foundational CS

20. Cause: Scoping

21. Cause: Type Instability

22. Vectorization
Loop

Cause: Vectorization

23. Frequency of Causes

24. Summary
Scientific Software
2
Cause#10: Data Structure Knowledge Gap
Category#9: Scope Concern
Global
Local
arahman@tntech.edu
akondrahman.github.io
@akondrahman

25. Backup

26. https://phys.org/news/2019-08-astronomers-earth-fingerprint-habitable-planets.html
https://www.icr.ac.uk/our-research/centres-and-collaborations/strategic-collaborations/cancer-research-uk-centre
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https://stackoverflow.com/questions/38399478/huge-memory-allocation-running-a-julia-function
https://miro.medium.com/max/4000/1*nkLi2YLBO3xys_dehSXoQw.png
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https://stackoverflow.com/questions/41203425/why-is-julia-allocating-so-much-memory
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https://miro.medium.com/max/1648/1*Q_UZeToStz8YY2oQGiUPqw.png
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