question about btt and blkparse

Hello Kejian -

The proper work-flow is as follows:

(1) blktrace -d /dev/sda

(2) blkparse -i sda.blktrace.0 -o o.parse -d bp.bin

(3) btt -i bp.bin -p o.btt

'btt' runs on the binary output from blkparse (the '-d bp.bin' in step
2) - not directly from the x.blktrace.y files generated by blktrace. When you do it in this order, you get the correct stamps from btt:

  8,0  :     0.000281229 Q    3368431+8
             0.000282543 M    3368431+8
             0.000387733 D    3368407+112
             0.011695204 C    3368407+112

which can be found in o.parse:

  8,0    0       13     0.000281229   461  Q   W 3368431 + 8 [kjournald]
  8,0    0       14     0.000282543   461  M   W 3368431 + 8 [kjournald]
...
  8,0    0       46     0.000387733   461  D   W 3368407 + 112 [kjournald]
  8,0    0       47     0.011695204     0  C   W 3368407 + 112 [0]

Regards,
Alan