hdparm.strace

jmb@zen:~/xfer$ time sudo strace -tT -o /tmp/strace.hdparm hdparm -t /dev/mapper/sys0-root                                                                                                                                                                                                      /dev/mapper/sys0-root:                                                                                                                           HDIO_DRIVE_CMD(identify) failed: Inappropriate ioctl for device                                                                                 Timing buffered disk reads: 3394 MB in  3.00 seconds = 1131.26 MB/sec                                                                                                                                                                                                                          real    8m26.623s                                                                                                                               user    0m0.100s                                                                                                                                sys     0m1.850s    
/dev/mapper/sys0-root:
HDIO_DRIVE_CMD(identify) failed: Inappropriate ioctl for device
Timing buffered disk reads: 3394 MB in  3.00 seconds = 1131.26 MB/sec
real    8m26.623s
user    0m0.100s
sys     0m1.850s

23:50:11 execve("/sbin/hdparm", ["hdparm", "-t", "/dev/mapper/sys0-root"], 0x7ffd0b643c58 /* 17 vars */) = 0 <0.000213>
...
23:50:11 openat(AT_FDCWD, "/dev/mapper/sys0-root", O_RDONLY|O_NONBLOCK) = 3 <0.000021>
23:50:11 write(1, "/dev/mapper/sys0-root:\n", 23) = 23 <0.000011>
... 200ish lines of status probe / setup
23:50:11 sync()                         = 0 <99.261508>
23:51:51 clock_nanosleep(CLOCK_REALTIME, 0, {tv_sec=3, tv_nsec=0}, 0x7fff9eea73b0) = 0 <3.000138>
23:51:54 write(1, " Timing buffered disk reads: ", 29) = 29 <0.000023>
...
... 3400 lines of read(3,...) and getitimer()
23:51:57 getitimer(ITIMER_REAL, {it_interval={tv_sec=1000, tv_usec=0}, it_value={tv_sec=996, tv_usec=999759}}) = 0 <0.000008>
23:51:57 write(1, "3394 MB in  3.00 seconds = 1131."..., 42) = 42 <0.000016>
23:51:57 munlockall()                   = 0 <0.006417>
23:51:57 munmap(0x7f1cd62ca000, 2097152) = 0 <0.000134>
23:51:57 sync()                         = 0 <147.874626>
23:54:25 fsync(3)                       = 0 <0.002552>
23:54:25 fdatasync(3)                   = 0 <0.000117>
23:54:25 sync()                         = 0 <167.969618>
23:57:13 ioctl(3, BLKFLSBUF)            = 0 <0.219426>
23:57:13 ioctl(3, HDIO_DRIVE_CMD, 0)    = -1 ENOTTY (Inappropriate ioctl for device) <0.000014>
23:57:13 sync()                         = 0 <85.257365>
23:58:38 close(3)                       = 0 <0.000017>
23:58:38 exit_group(0)                  = ?
23:58:38 +++ exited with 0 +++