1 The code in this directory is used to process data from the mmc tracepoints
2 in the kernel. To turn on mmc tracing, do this:
4 adb shell echo 1 >/d/tracing/events/mmc/enable
5 adb shell echo 1 >/d/tracing/tracing_on
9 adb pull /d/tracing/trace
11 To turn it back off, do:
13 adb shell echo 0 >/d/tracing/tracing_enabled
15 The output is in a form of start/stop pairs. The ops with rw in the name are
16 read or write ops, and the ones with erase in the name are the various erase
19 The mmc_trace_reduce script will take the output from the kernel, and convert it
20 to a single line per event, which includes the duration of the event.
22 This can then be fed into other tools for further analysis.
24 The file mmc_trace_sample_data contains sample mmc trace data from a Nexus 10.
25 It includes read, write and discard entries. The discard entries came from
26 invoking fstrim in vold with "vdc fstrim dotrim".