APFS in Detail: Data Integrity

This series of posts covers APFS, Apple’s new filesystem announced at WWDC 2016. See the first post for the table of contents. Data Integrity Arguably the most important job of a file system is preserving data integrity. Here’s my data, don’t lose it, don’t change it. If file systems could be trusted absolutely then the “only” reason [...]

Posted on June 19, 2016 at 7:37 pm by ahl · Permalink · 41 Comments
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On RAID-6 recovery

RAID algorithms have become a particular fascination of mine, and I recently read a very interesting paper that describes an optimization for RAID reconstruction (by Xiang, Xu, Lui, Chang, Pan, and Li). Before writing double- and triple-parity RAID algorithms for ZFS, I spent a fair bit of time researching the subject and have stayed interested [...]

Posted on September 21, 2011 at 10:33 pm by ahl · Permalink · One Comment
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What is RAID-Z?

The mission of ZFS was to simplify storage and to construct an enterprise level of quality from volume components by building smarter software — indeed that notion is at the heart of the 7000 series. An important piece of that puzzle was eliminating the expensive RAID card used in traditional storage and replacing it with [...]

Posted on July 21, 2010 at 11:46 pm by ahl · Permalink · 8 Comments
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