Performance Characterization of Suricata's Thread Models

In a previous project my fellow Amit Sheoran and I examined how well Suricata IDS runs inside Docker container and virtual machine environments. In April 2017, we further examined Suricata’s various thread models, as a project for Purdue CS525 Parallel Computing course. In this article we first introduce the thread models, and then compare them in terms of performance and resource utilization. Suricata’s Multi-Thread Architecture Compared to Snort IDS, the biggest feature of Suricata is that it adopts multi-threaded design to achieve high performance. Continue reading

Benchmarking Suricata in Different Isolation Systems Using TCPreplay

Containers like LXC are becoming a popular solution to program isolation. Compared to virtual machines (VM), containers tend to have less resource overhead and higher performance, which makes it interesting to explore how much benefit we can get from deploying virtual network functions (VNF) with containers instead of VMs. Therefore, we conducted an experiment in which we compared performance and resource usage of Suricata, a popular multi-threaded IDS program, in bare metal, Docker container, and virtual machine setups, and in different load levels and resource allocation configurations.

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gitlab-ag - Combining Git and Autograding

Planned in December 2014 and first released in January 2015, gitlab-ag is a project that aims to enhance GitLab, an open-source GitHub-like system, for educational use. The primary goal is to facilitate batch operations on GitLab and integrate automated grading mechanism, thereby replacing the AutoGrader system used in the past. It runs as a standalone website that manipulates GitLab API. GitHub Repository: https://github.com/xybu/gitlab-ag Documentation: https://github.com/xybu/gitlab-ag/blob/master/README.md License: GPLv2 Features Import / delete users in batch: import students (GitLab users) from CSV when a new semester starts, and delete all users after semester ends. Continue reading

Checking Memory Leakage of Student Programs

So far my assignment grading system uses a legacy (and buggy) library written by some former TA to check memory leakage of student programs. Now that it’s time for a major OS upgrade (Ubuntu 14.04), this solution exposed more bugs. Time to retire it and make my own ones.

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Purdue CS240 Autograder

For historical curiosity, this page records the work of Autograder, an automated grading platform used in Purdue CS240 “Programming in C” course. Students submit code for grading and later receive grades. This platform encouraged students to try achieving best score and also greatly reduced TAs’ workload. In Fall 2014 a new project gitlab-ag, based on GitLab, replaced Autograder. Autograder has been deprecated. The purpose of this page is to summarize the knowledge and experience gained from this project so that we make better things in the future. Continue reading