#!/usr/bin/stap

global reads, writes, total_io

probe vfs.read.return {
    reads[execname()] <<< bytes_read
    total_io[execname()] <<< bytes_read
}

probe vfs.write.return {
    writes[execname()] <<< bytes_written
    total_io[execname()] <<< bytes_written
}

# print top 10 IO processes every 5 seconds
probe timer.s(5) {
    printf ("%16s\t%10s\t%10s\n", "Process", "KB Read", "KB Written")
    foreach (name in total_io @sum- limit 10)
        printf("%16s\t%10d\t%10d\n", name,
               @sum(reads[name])/1024, @sum(writes[name])/1024)
    delete reads
    delete writes
    delete total_io
    print("\n")
}