Jung-Sang Ahn
안정상 (in Korean)
Software Engineer at Couchbase.
LinkedIn
Github
Resume (May, 2017)
Interests
- Indexing systems, file systems, storage systems, operating systems,
embedded systems.
- Problem solving, optimizing performance.
- Electric/acoustic guitar, finger-style guitar, band session,
song writing, recording/mixing/mastering.
- Snowboarding, go-kart.
Employment and Education
- Senior Software Engineer,
Couchbase,
2015 - present.
- Ph.D. in
Computer Science,
KAIST,
2010 - 2015.
- M.S. in
Computer Science,
KAIST,
2008 - 2010.
- B.S. in
Computer Science,
KAIST,
2004 - 2008.
- Presidential scholarship, the Korean government.
- Daejeon Science High School,
2002 - 2004.
Experiences
Software Engineer at Couchbase
- Storage layer improvement
- Designing/revising storage engine (fetching/storing key-value
pairs from/to disks) architecture.
- Optimizing disk I/O patterns.
- ForestDB
project
Research Assistant at KAIST
- UX-oriented mobile software platform
- A huge academic project in collaboration of 11 graduate school
laboratories and 2 companies including LG electronics,
funded by the Korean government.
- Worked on core mobile kernel part,
designed and developed a lightweight encryption file system
for Android platform.
- Paper:
Low-Overhead User Data Protection for Smartphones
using Plaintext Cache, IEEE Most 2013.
- Development of a basis technology for trustworthy computing
- Funded by the Korean government.
- Exploiting object-based interface for SSDs
- A high-performance FTL for large-capacity flash SSDs
- Development of environment for ubiquitous/embedded system software
- Research on development tool for next-generation flash memory.
- Funded by the Korean government.
Teaching Assistant at KAIST
- CS310 Embedded Computer Systems (won TA Excellence Award), Fall 2010.
- CS211 Digital System and Lab, Spring 2010.
- CS330 Operating System and Lab (won TA Excellence Award), Fall 2009.
- CS330 Operating System and Lab, Spring 2009.
- CS330 Operating System and Lab, Fall 2008.
- CS320 Programming Language, Spring 2008.
Personal Projects
-
Generic Skiplist container
- Skiplist implementation that can be used as set or map,
containing any type of data.
- Completely lock-free for concurrent readers and writers.
- Scalable throughput according to the number of threads.
-
Partial lock
- Grab a Lock on a small part of a large shared data, without
blocking other locks on non-overlapping parts.
-
C-style generic AVL-tree container
- An ordered index that can be used as set or map,
containing any type of data.
- Can be used in pure C.
- Up to 3x faster than STL set or map.
Publications and Patents
-
ForestDB: A Fast Key-Value Storage System for Variable-Length String
Keys
Jung-Sang Ahn, Chiyoung Seo, Ravi Mayuram, Rahim Yaseen,
Jin-Soo Kim, and Seungryoul Maeng
IEEE Transactions on Computers, 2016.
-
Low-Overhead User Data Protection for Smartphones using
Plaintext Cache
Jung-Sang Ahn and Seungryoul Maeng
Mobile Security Technologies (IEEE Symposium on Security and Privacy),
2013.
-
μ*-Tree: An Ordered Index Structure for NAND Flash Memory with
Adaptive Page Layout Scheme
Jung-Sang Ahn, Dongwon Kang, Dawoon Jung, Jin-Soo Kim,
and Seungryoul Maeng
IEEE Transactions on Computers, 2013.
-
Indexing Method for Flash Memory
Jaesoo Lee, Jung-Sang Ahn, Jin-Soo Kim, and Dawoon Jung
Patent Filed No. 13/273,501 (October 4, 2011), United States.
-
Indexing Method for Flash Memory
Jaesoo Lee, Jung-Sang Ahn, Jin-Soo Kim, and Dawoon Jung
Patent Filed No. 10-2010-0100464 (October 14, 2010), Korea.
Honors and Awards
-
Third Place, ACM SIGMOD Programming Contest, 2012.
A Multi-Dimensional Indexing System
-
Finalist, ACM SIGMOD Programming Contest, 2011.
A Durable Main-Memory Index Using Flash
-
Bronze Prize, Samsung Humantech Paper Award, 2008.
-
Silver Prize, Samsung Humantech Paper Award, 2004.
-
Honorable Mention, Samsung Humantech Paper Award, 2003.
-
Gold Medal, KOI (Korea Olympiad in Informatics), 2001.
Contact Information