This is a small Python script that can be invoked multiple times. Each time you invoke it, it tells you how much various disk statistics for a given partition have changed since the last invocation.
It depends on the /sys/dev/block/<major>:<minor>/stat file provided by Linux.
Example usage:
$ python3 disk_stat_diff.py sda5
Storing stats for the first time.
$ dd if=/dev/zero of=/data/foo bs=4096 count=1
1+0 records in
1+0 records out
4096 bytes (4.1 kB, 4.0 KiB) copied, 0.000172019 s, 23.8 MB/s
$ python3 disk_stat_diff.py sda5
Difference over the past 0.02 second(s).
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| stat | diff | avg |
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| read_ios | 0 | 0.0 |
| read_merges | 0 | 0.0 |
| read_sectors | 0 | 0.0 |
| read_ticks | 0 | 0.0 |
| write_ios | 1 | 40.79 |
| write_merges | 0 | 0.0 |
| write_sectors | 8 | 326.32 |
| write_ticks | 0 | 0.0 |
| in_flight | 0 | 0.0 |
| io_ticks | 4 | 163.16 |
| time_in_queue | 0 | 0.0 |
| discard_ios | 0 | 0.0 |
| discard_merges | 0 | 0.0 |
| discard_sectors | 0 | 0.0 |
| discard_ticks | 0 | 0.0 |
| flush_ios | 0 | 0.0 |
| flush_ticks | 0 | 0.0 |
| read_bytes | 0 | 0.0 |
| write_bytes | 4096 | 167073.84 |
| discard_bytes | 0 | 0.0 |
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