May 7, 2009
ZFS - the last word in file systems
By Neil Perrin.
ZFS is a new file system in Solaris 10. It was written from scratch to deliver provable data integrity; immense capacity; excellent performance; and simple administration. ZFS is based on pooled storage that eliminates traditional volumes. Probably the most compelling feature of ZFS is its end-to-end data integrity. No longer is bad data returned to the user or bad meta data used internally. When coupled with redundancy (mirroring or RAID) this provides self healing. Internally, ZFS uses a transactional architecture to ensure the pool is always self consistent. No more fsck! ZFS gets its high performance from its copy-on-write design (which turns random writes into sequential writes), multiple blocks sizes, dynamic striping and intelligent prefetch. Finally, many customers are praising the simple easy to use and understand user interface that ZFS provides for managing their storage.
Neil is a Staff Engineer in the Solaris Software Group and has been with Sun for over 13 years. He has been working in the ZFS development group almost from it's inception over 6 years ago. Neil has been primarily responsible for the ZFS Intent Log (ZIL), which is a critical component in ensuring synchronous semantics for Databases and NFS. He has also got his fingers dirty in many other areas of the ZFS kernel code, such as range locking, sparse file and generic DNLC support.
Prior to ZFS, Neil worked on UFS and in particular on logging (journaling) functionality and performance. He has a BSc (Hons) degree in Computer Science from Reading University, England.