Log-structured file system: Difference between revisions

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To maximize write throughput, a log-structured file system treats the disk as a circular log and writes sequentially to the head of the log. This has the side effect of creating multiple, chronologically-advancing versions of both file data and meta-data. This log is undoable.

Due to the rotational latency of disk access, write operations in traditional file systems are slow and do not fully utilize data bus capacities. With long sequential writes, log-structured file systems more fully utilize data bus capacities.

It is seen that data bus capacity is not fully utilize when transfering data. This acts as bottleneck for write operations which are slow in traditional file system due to rotational latency of disk. Log-structured file system provides a way in which we can perform writes faster in sequential form.

Such filesystems<ref name="rosenblum92">Rosenblum, Mendel and Ousterhout, John K. (February 1992) - "[http://www.hhhh.org/perseant/lfs/lfsSOSP91.ps.gz The Design and Implementation of a Log-Structured File System]". ''ACM Transactions on Computer Systems, Vol. 10 Issue 1''. pp26-52.</ref>: