YAFFS is a filesystem designed specifically for the characteristics of NAND flash. Its primary features are:
- Fast - much faster than alternatives
- Easily ported (currently ported to GNU/Linux, WinCE, eCOS, pSOS, VxWorks, and various bare-metal systems)
- Log structured, providing wear-levelling and making it very robust
- Supports various flash geometries including 2KB and 512-Byte page NAND flash chips
- Supports MLC and SLC flash
- Very fast mount - almost immediate startup
- Typically uses less RAM than comparable File Systems
- Flexible Licensing suitable for most circumstances
This page gives an overview of the project - what is available, how it works, how to use it, developer resources, and licensing options.
Simple
HOWTO for getting started with
YAFFS and using it as a root filesystem. If you just want the
quick start info - read this.
Notes on how to use Yaffs (Yaffs1) and some details of the internal structures - useful if you want to mess with the code. This document is included in the Yaffs1 download.
The initial specification for Yaffs version 2. Describes the development of Yaffs to deal with next-generation NAND chips which have larger (2Kb) pages and don’t allow page rewrites. This newer design is be significantly faster (write: 1.5x-5x, delete: 4x, garbage collection: 2x) and has 25-50% lower RAM footfrint.
The initial specification for Yaffs. Circa 2002. Details of the filing system, including short backgrounder. Read this if you want to know what it is, what it does and how it works. This specification does not cover Yaffs2.
The purpose of this document is to describe how to bring up Yaffs2 on a board previously unsupported using the Yaffs Direct Interface, with an example using eCos on a Balloon board.
Attached is a PDF with slides from the Yaffs talk at CELF’s Embedded Linux Conference Europe 2007. If you are able to view Ogg Theora video files, the talk is also online. Ogg Theora is a Free video format. Free players are available for all platforms. See the list here. If in doubt, VLC is probably available for your operating system.
If you prefer to go straight to the .pdf if clides click http://www.yaffs.net/sites/yaffs.net/files/yaffs.pdf
This provides a link to a PDF of a paper by Taiwanese scholars.
If you are trying to decide between Yaffs and JFFS2 then this note will give you an idea of the relative advantages of each.
