The B ε-tree File System, or BetrFS, (pronounced " better eff ess ") is the first in-kernel file system to use a write-optimized index. Write optimized indexes (WOIs) are promising building blocks for storage systems because of their potential to implement both microwrites and large scans efficiently. Previous work on WOI-based file systems has shown… (More)
Applications frequently request file system operations that traverse the file system directory tree, such as opening a file or reading a file's metadata. As a result, caching file system directory structure and metadata in memory is an important performance optimization for an OS kernel. This paper identifies several design principles that can… (More)
The <b><i>B<sup>ϵ</sup>-tree File System</i></b>, or B<i>e</i>trFS (pronounced “better eff ess”), is the first in-kernel file system to use a write-optimized data structure (WODS). WODS are promising building blocks for storage systems because they support both microwrites and large scans efficiently. Previous WODS-based file systems have… (More)
File systems that employ write-optimized dictionaries (WODs) can perform random-writes, metadata updates, and recursive directory traversals orders of magnitude faster than conventional file systems. However, previous WOD-based file systems have not obtained all of these performance gains without sacrificing performance on other operations, such as file… (More)
Porcine circovirus 2 (PCV2) strain 102 belongs to the PCV2b-1C subtype, and its sole structural protein (Cap) exhibits high homology with that of other PCV2b isolates reported in South Korea, China, and the United States. Strain 102 contains a new mutation (R37H) in the domain of the nuclear localization signal (NLS) of the Cap.
This paper introduces versioned programming, a technique that can be used to convert pointer-based data structures into efficient, lock-free implementations. Versioned programming allows arbitrary composition of pointer modifications. Taking linked-lists as an example, VLISTs, or versioned lists, support features missing in other lock-free implementations,… (More)
The complete genome of porcine circovirus type 2 (PCV2) strain YiY-3-2-H5 contains a cytidine insertion at position 962 in open reading frame 1. This insertion causes a reading frameshift of the rep gene, and thereafter a premature stop codon is present at the 3' terminal end of this gene.