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04. [20p] Monitor I/O with vmstat and iostat
We said in the beginning that the disk I/O subsystems are the slowest part of any system. This is why the I/O monitoring is so important, maximizing the performance of the slowest part of a system resulting in an improvement of the performance of the entire system.
[10p] Task A - Script
Write a script that reads the data into memory and generates a text file 500 times larger, by concatenating the contents of the following novel olivertwist.txt to itself.
[10p] Task B - Monitoring behaviour
Now we want to analyze what is happening with the I/O subsystem during an expensive operation. Monitor the behavior of the system while running your script using vmstat and iostat.
Understanding vmstat IO section:
- bi - column reports the number of blocks received (or “blocks in”) from a disk per second.
- bo - column reports the number of blocks sent (“blocks out”) to a disk per second.
