Contact
I'm now working at Google Enterprise and you can send email to my_usual_username@google.com.

Research Interests

I am interested in software systems related areas, with particular interests in memory management and data optimization. I study operating systems, runtime systems, programming languages and focus on the cooperation between these components, with a goal of improving the performance, scalability and robustness of software systems. My advisor is Prof. Emery Berger.

Projects

Hierarchical Hashing

Cooperative Memory Management (PhD synthesis project)

Scheduler Aware Virtual Memory Management (SAVMM) (led by Emery Berger, Scott Kaplan and Prashant Shenoy)

Cooperative Robust Automatic Memory Management (CRAMM) (led by Emery Berger, Eliot Moss and Scott Kaplan)

Publications

A Locality-Improving Dynamic Memory Allocator (pdf)
Yi Feng and Emery Berger
3rd Annual ACM SIGPLAN Workshop on Memory Systems Performance (MSP 2005)

Garbage Collection without Paging (pdf)
Matthew Hertz, Yi Feng and Emery Berger
ACM SIGPLAN 2005 Conference on Programming Language Design and Implementation (PLDI 2005)

Software

Vam
I developed this dynamic memory allocator which transparently improves the application's data locality in both the cache level and the virtual memory level. It is a replacement for the widely used malloc/free functions in the C library and improves application performance over the state-of-the-art allocators with varied memory sizes. This memory manager can additionally communicate with the (VMSig-patched) Linux kernel under memory pressure and reduce the performance degradation caused by paging. Vam is available as part of the heaplayers package.

VMSig
I developed this virtual memory communication patch for the Linux kernel. It allows the user applications to register and receive signals from the OS kernel on VM paging events. With the extended functionality of the madvise system call, the user applications can help improve the efficiency of VM management in the kernel. It also fixes the problem of the mincore system call in the stock kernel where mincore does not work with anonymous pages. This patch was originally developed for Linux 2.4 (download the kernel patch for Linux 2.4.24) and later ported to Linux 2.6 (download the kernel patch for Linux 2.6.14 and the header file for the new system interface).