Alireza Haghdoost <haghdoost@xxxxxxxxx> writes:
> On Wed, Dec 4, 2013 at 10:02 AM, Lakshmi <sendtold@xxxxxxxxx> wrote:
>> Hi,
>>
>> I ran a blktrace with -a read mask and when i parsed it to txt
>> file,Along with Reads (R) I also see lots of Ns in the RWBS field.
>
> I think the N events indicates that new data structure has been
> allocated for the request.
No. It's a trace Notify message, which is used for debugging.
>> What does this mean and how do I filter only the reads or writes in
>> this case?
You can use the filter mask option for blktrace:
FILTER MASKS
The following masks may be passed with the -a command line option, mul-
tiple filters may be combined via multiple -a command line options.
barrier: barrier attribute
complete: completed by driver
fs: requests
issue: issued to driver
pc: packet command events
queue: queue operations
read: read traces
requeue: requeue operations
sync: synchronous attribute
write: write traces
notify: trace messages <=========================
drv_data: additional driver specific trace
Cheers,
Jeff
--
To unsubscribe from this list: send the line "unsubscribe linux-btrace" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
