dust

dust is a pwru to trace io request

Why dust?

As we all know, io requests initiated by processes go through a long process before they finally hit the disk, during which the io request is handled by the kworker. This asynchronous processing makes it very difficult to track io, so we start with the io request and track the io request's lifecycle.

dust tracks the io request returned by blk_mq_alloc_request and monitors how long it runs in all functions that call struct request *, giving a clearer picture of the io request lifecycle.

TL;DR

Usage:

./dust -h
Usage: ./dust [options]
    Available options:
  -h, --help              show help
  -i, --interval uint32   set monitor time in seconds (default 10)
  -o, --ofile string      output file
  -p, --pid uint32        filter pid
  -v, --version           show version

Example: trace a process for 30 seconds.

sudo ./dust -p {the_process_you_want_to_trace} -i 30

TODO

• kprobe filters.
• kprobe.multi supports.
• output to files.