The filesystem buffer cache does both buffering and caching. Describe why buffering is needed. Describe how buffering can improve performance (potentially to the detriment of file system...

      

The filesystem buffer cache does both buffering and caching. Describe why buffering is
needed. Describe how buffering can improve performance (potentially to the detriment of file
system robustness). Describe how the caching component of the buffer cache improves
performance

  

Answers


Faith
Buffering is required in order to ensure that performance is not degraded as a file is sequentially read or
written to, perhaps from different parts of the physical disk, since a large number of the disk reads occur
before the file is actually “read” by the user (or in the case of writes, the data is flushed to disk long after individual “writes” occur). This minimises expensive disk I/O operations, because I/O occurs in
sequential bursts, but possibly at the detriment of robustness – for example if a power failure occurs, the
buffer cache is lost, and its contents were not written to disk. The caching component improves performance still, by storing frequently used parts of files in fast memory, minimising lengthy disk access times.
Titany answered the question on April 26, 2022 at 11:48


Next: What is the reference count field in the inode? You should consider its relationship to directory entries in you answer
Previous: What does flushd do on a UNIX system?

View More Operating Systems Questions and Answers | Return to Questions Index


Exams With Marking Schemes

Related Questions